diff --git a/cmake/tests.cmake b/cmake/tests.cmake
index 328074c0..245047fd 100644
--- a/cmake/tests.cmake
+++ b/cmake/tests.cmake
@@ -76,7 +76,8 @@ set(LIBLOOT_SRC_TESTS_INTERFACE_H_FILES
     "${CMAKE_SOURCE_DIR}/src/tests/api/interface/metadata/message_content_test.h"
     "${CMAKE_SOURCE_DIR}/src/tests/api/interface/metadata/plugin_cleaning_data_test.h"
     "${CMAKE_SOURCE_DIR}/src/tests/api/interface/metadata/plugin_metadata_test.h"
-    "${CMAKE_SOURCE_DIR}/src/tests/api/interface/metadata/tag_test.h")
+    "${CMAKE_SOURCE_DIR}/src/tests/api/interface/metadata/tag_test.h"
+    "${CMAKE_SOURCE_DIR}/src/tests/api/interface/plugin_interface_test.h")
 
 source_group(TREE "${CMAKE_SOURCE_DIR}/src/tests/api/internals"
     PREFIX "Source Files"
diff --git a/src/tests/api/interface/main.cpp b/src/tests/api/interface/main.cpp
index 9e42be34..9b217666 100644
--- a/src/tests/api/interface/main.cpp
+++ b/src/tests/api/interface/main.cpp
@@ -38,6 +38,7 @@
 #include "tests/api/interface/database_interface_test.h"
 #include "tests/api/interface/game_interface_test.h"
 #include "tests/api/interface/is_compatible_test.h"
+#include "tests/api/interface/plugin_interface_test.h"
 
 int main(int argc, char **argv) {
   ::testing::InitGoogleTest(&argc, argv);
diff --git a/src/tests/api/interface/plugin_interface_test.h b/src/tests/api/interface/plugin_interface_test.h
new file mode 100644
index 00000000..ed8da8ba
--- /dev/null
+++ b/src/tests/api/interface/plugin_interface_test.h
@@ -0,0 +1,486 @@
+/*  LOOT
+
+A load order optimisation tool for Oblivion, Skyrim, Fallout 3 and
+Fallout: New Vegas.
+
+Copyright (C) 2014-2016    WrinklyNinja
+
+This file is part of LOOT.
+
+LOOT is free software: you can redistribute
+it and/or modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation, either version 3 of
+the License, or (at your option) any later version.
+
+LOOT is distributed in the hope that it will
+be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with LOOT.  If not, see
+<https://www.gnu.org/licenses/>.
+*/
+
+#ifndef LOOT_TESTS_API_INTERFACE_PLUGIN_INTERFACE_TEST
+#define LOOT_TESTS_API_INTERFACE_PLUGIN_INTERFACE_TEST
+
+#include "loot/api.h"
+#include "tests/api/interface/api_game_operations_test.h"
+
+namespace loot::test {
+class PluginInterfaceTest : public ApiGameOperationsTest {
+protected:
+  PluginInterfaceTest() :
+      ApiGameOperationsTest(),
+      nonAsciiEsp(u8"non\u00C1scii.esp"),
+      otherNonAsciiEsp(u8"other non\u00C1scii.esp"),
+      blankArchive("Blank" + GetArchiveFileExtension(GetParam())),
+      blankSuffixArchive("Blank - Different - suffix" +
+                         GetArchiveFileExtension(GetParam())) {}
+
+  void SetUp() override {
+    ApiGameOperationsTest::SetUp();
+
+    handle_->LoadPlugins(GetInstalledPlugins(), false);
+
+    if (!supportsLightPlugins(GetParam())) {
+      ASSERT_NO_THROW(
+          std::filesystem::copy(dataPath / blankEsp, dataPath / blankEsl));
+    }
+    ASSERT_TRUE(std::filesystem::exists(dataPath / blankEsl));
+
+    // Make sure the plugins with non-ASCII filenames exists.
+    ASSERT_NO_THROW(std::filesystem::copy_file(
+        dataPath / blankEsp, dataPath / std::filesystem::u8path(nonAsciiEsp)));
+    ASSERT_NO_THROW(std::filesystem::copy_file(
+        dataPath / blankEsp,
+        dataPath / std::filesystem::u8path(otherNonAsciiEsp)));
+
+    // Copy across archive files.
+    std::filesystem::path blankMasterDependentArchive;
+    if (GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr ||
+        GetParam() == GameType::starfield) {
+      copyPlugin(getSourceArchivesPath(GetParam()), "Blank - Main.ba2");
+      copyPlugin(getSourceArchivesPath(GetParam()), "Blank - Textures.ba2");
+
+      blankMasterDependentArchive = "Blank - Master Dependent - Main.ba2";
+      std::filesystem::copy_file(
+          getSourceArchivesPath(GetParam()) / "Blank - Main.ba2",
+          dataPath / blankMasterDependentArchive);
+      ASSERT_TRUE(
+          std::filesystem::exists(dataPath / blankMasterDependentArchive));
+    } else if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw) {
+      touch(dataPath / blankArchive);
+
+      blankMasterDependentArchive = "Blank - Master Dependent.bsa";
+      touch(dataPath / blankMasterDependentArchive);
+    } else {
+      copyPlugin(getSourcePluginsPath(), blankArchive);
+
+      // Also create a copy for Blank - Master Dependent.esp to test overlap.
+      blankMasterDependentArchive = "Blank - Master Dependent.bsa";
+      std::filesystem::copy_file(getSourcePluginsPath() / blankArchive,
+                                 dataPath / blankMasterDependentArchive);
+      ASSERT_TRUE(
+          std::filesystem::exists(dataPath / blankMasterDependentArchive));
+    }
+
+    // Create dummy archive files.
+    touch(dataPath / blankSuffixArchive);
+
+    auto nonAsciiArchivePath =
+        dataPath / std::filesystem::u8path(u8"non\u00E1scii" +
+                                           GetArchiveFileExtension(GetParam()));
+    touch(dataPath / nonAsciiArchivePath);
+
+    auto nonAsciiPrefixArchivePath =
+        dataPath / std::filesystem::u8path(u8"other non\u00E1scii2 - suffix" +
+                                           GetArchiveFileExtension(GetParam()));
+    touch(dataPath / nonAsciiPrefixArchivePath);
+  }
+
+  std::shared_ptr<const PluginInterface> LoadPluginHeader(
+      std::string_view pluginName) {
+    handle_->LoadPlugins({std::filesystem::u8path(pluginName)}, true);
+
+    return handle_->GetPlugin(pluginName);
+  }
+
+  std::shared_ptr<const PluginInterface> LoadPlugin(
+      std::string_view pluginName) {
+    handle_->LoadPlugins({std::filesystem::u8path(pluginName)}, false);
+
+    return handle_->GetPlugin(pluginName);
+  }
+
+  std::string nonAsciiEsp;
+  std::string otherNonAsciiEsp;
+  std::string blankArchive;
+  std::string blankSuffixArchive;
+
+  std::shared_ptr<GameInterface> game_;
+
+private:
+  static std::string GetArchiveFileExtension(const GameType gameType) {
+    if (gameType == GameType::fo4 || gameType == GameType::fo4vr ||
+        gameType == GameType::starfield)
+      return ".ba2";
+    else
+      return ".bsa";
+  }
+};
+
+class TestPlugin : public PluginInterface {
+public:
+  std::string GetName() const override { return ""; }
+
+  std::optional<float> GetHeaderVersion() const override {
+    return std::optional<float>();
+  }
+
+  std::optional<std::string> GetVersion() const override {
+    return std::optional<std::string>();
+  }
+
+  std::vector<std::string> GetMasters() const override { return {}; }
+
+  std::vector<std::string> GetBashTags() const override { return {}; }
+
+  std::optional<uint32_t> GetCRC() const override {
+    return std::optional<uint32_t>();
+  }
+
+  bool IsMaster() const override { return false; }
+
+  bool IsLightPlugin() const override { return false; }
+
+  bool IsMediumPlugin() const override { return false; }
+
+  bool IsUpdatePlugin() const override { return false; }
+
+  bool IsBlueprintPlugin() const override { return false; }
+
+  bool IsValidAsLightPlugin() const override { return false; }
+
+  bool IsValidAsMediumPlugin() const override { return false; }
+
+  bool IsValidAsUpdatePlugin() const override { return false; }
+
+  bool IsEmpty() const override { return false; }
+
+  bool LoadsArchive() const override { return false; }
+
+  bool DoRecordsOverlap(const PluginInterface&) const override { return false; }
+};
+
+// Pass an empty first argument, as it's a prefix for the test instantation,
+// but we only have the one so no prefix is necessary.
+INSTANTIATE_TEST_SUITE_P(,
+                         PluginInterfaceTest,
+                         ::testing::ValuesIn(ALL_GAME_TYPES));
+
+TEST_P(PluginInterfaceTest,
+       shouldBeAbleToGetHeaderDataFromPluginLoadedHeaderOnly) {
+  const auto plugin = LoadPluginHeader(blankEsm);
+
+  EXPECT_EQ(blankEsm, plugin->GetName());
+  EXPECT_TRUE(plugin->GetMasters().empty());
+  if (GetParam() == GameType::openmw ||
+      GetParam() == GameType::oblivionRemastered) {
+    EXPECT_FALSE(plugin->IsMaster());
+  } else {
+    EXPECT_TRUE(plugin->IsMaster());
+  }
+  EXPECT_FALSE(plugin->IsEmpty());
+  EXPECT_EQ("5.0", plugin->GetVersion());
+
+  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw) {
+    EXPECT_FLOAT_EQ(1.2f, plugin->GetHeaderVersion().value());
+  } else if (GetParam() == GameType::tes4 ||
+             GetParam() == GameType::oblivionRemastered) {
+    EXPECT_FLOAT_EQ(0.8f, plugin->GetHeaderVersion().value());
+  } else if (GetParam() == GameType::starfield) {
+    EXPECT_FLOAT_EQ(0.96f, plugin->GetHeaderVersion().value());
+  } else {
+    EXPECT_FLOAT_EQ(0.94f, plugin->GetHeaderVersion().value());
+  }
+}
+
+TEST_P(PluginInterfaceTest, shouldBeAbleToGetAllDataFromFullyLoadedPlugin) {
+  const auto plugin = LoadPlugin(blankEsm);
+
+  EXPECT_EQ(blankEsm, plugin->GetName());
+  EXPECT_TRUE(plugin->GetMasters().empty());
+  if (GetParam() == GameType::openmw ||
+      GetParam() == GameType::oblivionRemastered) {
+    EXPECT_FALSE(plugin->IsMaster());
+  } else {
+    EXPECT_TRUE(plugin->IsMaster());
+  }
+  EXPECT_FALSE(plugin->IsEmpty());
+  EXPECT_EQ("5.0", plugin->GetVersion());
+
+  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw) {
+    EXPECT_FLOAT_EQ(1.2f, plugin->GetHeaderVersion().value());
+  } else if (GetParam() == GameType::tes4 ||
+             GetParam() == GameType::oblivionRemastered) {
+    EXPECT_FLOAT_EQ(0.8f, plugin->GetHeaderVersion().value());
+  } else if (GetParam() == GameType::starfield) {
+    EXPECT_FLOAT_EQ(0.96f, plugin->GetHeaderVersion().value());
+  } else {
+    EXPECT_FLOAT_EQ(0.94f, plugin->GetHeaderVersion().value());
+  }
+
+  EXPECT_EQ(blankEsmCrc, plugin->GetCRC());
+}
+
+TEST_P(PluginInterfaceTest,
+       loadingANonMasterPluginShouldReadTheMasterFlagAsFalse) {
+  const auto plugin = LoadPluginHeader(blankMasterDependentEsp);
+
+  EXPECT_FALSE(plugin->IsMaster());
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    isLightPluginShouldBeTrueForAPluginWithEslFileExtensionForFallout4AndSkyrimSe) {
+  const auto plugin1 = LoadPluginHeader(blankEsm);
+  const auto plugin2 = LoadPluginHeader(blankMasterDependentEsp);
+
+  EXPECT_FALSE(plugin1->IsLightPlugin());
+  EXPECT_FALSE(plugin2->IsLightPlugin());
+
+  if (GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr ||
+      GetParam() == GameType::tes5se || GetParam() == GameType::tes5vr ||
+      GetParam() == GameType::starfield) {
+    const auto plugin3 = LoadPluginHeader(blankEsl);
+    EXPECT_TRUE(plugin3->IsLightPlugin());
+  }
+}
+
+TEST_P(PluginInterfaceTest,
+       isMediumPluginShouldBeTrueForAMediumFlaggedPluginForStarfield) {
+  if (GetParam() != GameType::starfield) {
+    auto bytes = ReadFile(dataPath / blankEsm);
+    bytes[9] = 0x4;
+    WriteFile(dataPath / blankEsm, bytes);
+  }
+
+  const auto& pluginName =
+      GetParam() == GameType::starfield ? blankMediumEsm : blankEsm;
+  const auto plugin = LoadPluginHeader(pluginName);
+
+  EXPECT_EQ(GetParam() == GameType::starfield, plugin->IsMediumPlugin());
+}
+
+TEST_P(PluginInterfaceTest,
+       isUpdatePluginShouldOnlyBeTrueForAStarfieldUpdatePlugin) {
+  auto bytes = ReadFile(dataPath / blankMasterDependentEsp);
+  bytes[9] = 0x2;
+  WriteFile(dataPath / blankMasterDependentEsp, bytes);
+
+  const auto plugin1 = LoadPluginHeader(blankEsp);
+  const auto plugin2 = LoadPluginHeader(blankMasterDependentEsp);
+
+  EXPECT_FALSE(plugin1->IsUpdatePlugin());
+  EXPECT_EQ(GetParam() == GameType::starfield, plugin2->IsUpdatePlugin());
+}
+
+TEST_P(PluginInterfaceTest,
+       isBlueprintPluginShouldOnlyBeTrueForAStarfieldBlueprintPlugin) {
+  SetBlueprintFlag(dataPath / blankMasterDependentEsp);
+
+  const auto plugin1 = LoadPluginHeader(blankEsp);
+  const auto plugin2 = LoadPluginHeader(blankMasterDependentEsp);
+
+  EXPECT_FALSE(plugin1->IsBlueprintPlugin());
+  EXPECT_EQ(GetParam() == GameType::starfield, plugin2->IsBlueprintPlugin());
+}
+
+TEST_P(PluginInterfaceTest, loadingAPluginWithMastersShouldReadThemCorrectly) {
+  const auto plugin = LoadPluginHeader(blankMasterDependentEsp);
+
+  if (GetParam() == GameType::starfield) {
+    EXPECT_EQ(std::vector<std::string>({blankFullEsm}), plugin->GetMasters());
+  } else {
+    EXPECT_EQ(std::vector<std::string>({blankEsm}), plugin->GetMasters());
+  }
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveThatExactlyMatchesAnEsmFileBasenameShouldReturnTrueForAllGamesExceptMorrowindAndOblivion) {
+  bool loadsArchive = LoadPluginHeader(blankEsm)->LoadsArchive();
+
+  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw ||
+      GetParam() == GameType::tes4 ||
+      GetParam() == GameType::oblivionRemastered)
+    EXPECT_FALSE(loadsArchive);
+  else
+    EXPECT_TRUE(loadsArchive);
+}
+
+#ifdef _WIN32
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveThatExactlyMatchesANonAsciiEspFileBasenameShouldReturnTrueForAllGamesExceptMorrowindAndStarfield) {
+  bool loadsArchive = LoadPluginHeader(nonAsciiEsp)->LoadsArchive();
+
+  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw ||
+      GetParam() == GameType::starfield)
+    EXPECT_FALSE(loadsArchive);
+  else
+    EXPECT_TRUE(loadsArchive);
+}
+#endif
+
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveThatExactlyMatchesAnEspFileBasenameShouldReturnTrueForAllGamesExceptMorrowind) {
+  bool loadsArchive = LoadPluginHeader(blankEsp)->LoadsArchive();
+
+  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw)
+    EXPECT_FALSE(loadsArchive);
+  else
+    EXPECT_TRUE(loadsArchive);
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheEsmFileBasenameShouldReturnTrueForOnlyTheFalloutGames) {
+  bool loadsArchive = LoadPluginHeader(blankDifferentEsm)->LoadsArchive();
+
+  if (GetParam() == GameType::fo3 || GetParam() == GameType::fonv ||
+      GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr) {
+    EXPECT_TRUE(loadsArchive);
+  } else {
+    EXPECT_FALSE(loadsArchive);
+  }
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheEspFileBasenameShouldReturnTrueForOnlyOblivionAndTheFalloutGames) {
+  bool loadsArchive = LoadPluginHeader(blankDifferentEsp)->LoadsArchive();
+
+  if (GetParam() == GameType::tes4 || GetParam() == GameType::fo3 ||
+      GetParam() == GameType::fonv || GetParam() == GameType::fo4 ||
+      GetParam() == GameType::fo4vr ||
+      GetParam() == GameType::oblivionRemastered) {
+    EXPECT_TRUE(loadsArchive);
+  } else {
+    EXPECT_FALSE(loadsArchive);
+  }
+}
+
+#ifdef _WIN32
+TEST_P(
+    PluginInterfaceTest,
+    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheNonAsciiEspFileBasenameShouldReturnTrueForOnlyOblivionAndTheFalloutGames) {
+  bool loadsArchive = LoadPluginHeader(otherNonAsciiEsp)->LoadsArchive();
+
+  if (GetParam() == GameType::tes4 || GetParam() == GameType::fo3 ||
+      GetParam() == GameType::fonv || GetParam() == GameType::fo4 ||
+      GetParam() == GameType::fo4vr ||
+      GetParam() == GameType::oblivionRemastered) {
+    EXPECT_TRUE(loadsArchive);
+  } else {
+    EXPECT_FALSE(loadsArchive);
+  }
+}
+#endif
+
+TEST_P(PluginInterfaceTest,
+       loadsArchiveShouldReturnFalseForAPluginThatDoesNotLoadAnArchive) {
+  const auto pluginName = GetParam() == GameType::starfield
+                              ? blankDifferentEsp
+                              : blankDifferentMasterDependentEsp;
+  bool loadsArchive = LoadPluginHeader(pluginName)->LoadsArchive();
+
+  EXPECT_FALSE(loadsArchive);
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    isValidAsLightPluginShouldReturnTrueOnlyForASkyrimSEOrFallout4PluginWithNewFormIdsBetween0x800And0xFFFInclusive) {
+  bool valid = LoadPlugin(blankEsm)->IsValidAsLightPlugin();
+  if (GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr ||
+      GetParam() == GameType::tes5se || GetParam() == GameType::tes5vr ||
+      GetParam() == GameType::starfield) {
+    EXPECT_TRUE(valid);
+  } else {
+    EXPECT_FALSE(valid);
+  }
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    isValidAsMediumPluginShouldReturnTrueOnlyForAStarfieldPluginWithNewFormIdsBetween0And0xFFFFInclusive) {
+  bool valid = LoadPlugin(blankEsm)->IsValidAsMediumPlugin();
+  if (GetParam() == GameType::starfield) {
+    EXPECT_TRUE(valid);
+  } else {
+    EXPECT_FALSE(valid);
+  }
+}
+
+TEST_P(
+    PluginInterfaceTest,
+    IsValidAsUpdatePluginShouldOnlyReturnTrueForAStarfieldPluginWithNoNewRecords) {
+  const auto sourcePluginName =
+      GetParam() == GameType::starfield ? blankFullEsm : blankEsp;
+  const auto updatePluginName = GetParam() == GameType::starfield
+                                    ? blankMasterDependentEsp
+                                    : blankDifferentPluginDependentEsp;
+
+  std::vector<std::shared_ptr<const PluginInterface>> plugins;
+  plugins.push_back(LoadPlugin(sourcePluginName));
+  plugins.push_back(LoadPlugin(updatePluginName));
+
+  EXPECT_FALSE(plugins[0]->IsValidAsUpdatePlugin());
+  EXPECT_EQ(GetParam() == GameType::starfield,
+            plugins[1]->IsValidAsUpdatePlugin());
+}
+
+TEST_P(PluginInterfaceTest,
+       doRecordsOverlapShouldReturnFalseIfTheArgumentIsNotAPluginObject) {
+  const auto plugin1 = LoadPlugin(blankEsm);
+  TestPlugin plugin2;
+
+  EXPECT_FALSE(plugin1->DoRecordsOverlap(plugin2));
+}
+
+TEST_P(PluginInterfaceTest,
+       doRecordsOverlapShouldReturnFalseForTwoPluginsWithOnlyHeadersLoaded) {
+  const auto plugin1 = LoadPluginHeader(blankEsm);
+  const auto plugin2 = LoadPluginHeader(blankMasterDependentEsm);
+
+  EXPECT_FALSE(plugin1->DoRecordsOverlap(*plugin2));
+  EXPECT_FALSE(plugin2->DoRecordsOverlap(*plugin1));
+}
+
+TEST_P(PluginInterfaceTest,
+       doRecordsOverlapShouldReturnFalseIfThePluginsHaveUnrelatedRecords) {
+  const auto plugin1 = LoadPlugin(blankEsm);
+  const auto plugin2 = LoadPlugin(blankEsp);
+
+  EXPECT_FALSE(plugin1->DoRecordsOverlap(*plugin2));
+  EXPECT_FALSE(plugin2->DoRecordsOverlap(*plugin1));
+}
+
+TEST_P(PluginInterfaceTest,
+       doRecordsOverlapShouldReturnTrueIfOnePluginOverridesTheOthersRecords) {
+  const auto plugin1Name =
+      GetParam() == GameType::starfield ? blankFullEsm : blankEsm;
+
+  const auto plugin1 = LoadPlugin(plugin1Name);
+  const auto plugin2 = LoadPlugin(blankMasterDependentEsm);
+
+  EXPECT_TRUE(plugin1->DoRecordsOverlap(*plugin2));
+  EXPECT_TRUE(plugin2->DoRecordsOverlap(*plugin1));
+}
+
+}
+
+#endif
diff --git a/src/tests/api/internals/plugin_test.h b/src/tests/api/internals/plugin_test.h
index 4c7e198a..b9151cba 100644
--- a/src/tests/api/internals/plugin_test.h
+++ b/src/tests/api/internals/plugin_test.h
@@ -278,67 +278,6 @@ TEST_P(PluginTest, loadingShouldHandleNonAsciiFilenamesCorrectly) {
   EXPECT_EQ(nonAsciiEsp, plugin.GetName());
 }
 
-TEST_P(PluginTest, loadingHeaderOnlyShouldReadHeaderData) {
-  Plugin plugin(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true);
-
-  EXPECT_EQ(blankEsm, plugin.GetName());
-  EXPECT_TRUE(plugin.GetMasters().empty());
-  if (GetParam() == GameType::openmw ||
-      GetParam() == GameType::oblivionRemastered) {
-    EXPECT_FALSE(plugin.IsMaster());
-  } else {
-    EXPECT_TRUE(plugin.IsMaster());
-  }
-  EXPECT_FALSE(plugin.IsEmpty());
-  EXPECT_EQ("5.0", plugin.GetVersion());
-
-  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw) {
-    EXPECT_FLOAT_EQ(1.2f, plugin.GetHeaderVersion().value());
-  } else if (GetParam() == GameType::tes4 ||
-             GetParam() == GameType::oblivionRemastered) {
-    EXPECT_FLOAT_EQ(0.8f, plugin.GetHeaderVersion().value());
-  } else if (GetParam() == GameType::starfield) {
-    EXPECT_FLOAT_EQ(0.96f, plugin.GetHeaderVersion().value());
-  } else {
-    EXPECT_FLOAT_EQ(0.94f, plugin.GetHeaderVersion().value());
-  }
-}
-
-TEST_P(PluginTest, loadingHeaderOnlyShouldNotReadFieldsOrCalculateCrc) {
-  Plugin plugin(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true);
-
-  EXPECT_FALSE(plugin.GetCRC());
-}
-
-TEST_P(PluginTest, loadingWholePluginShouldReadHeaderData) {
-  Plugin plugin(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true);
-
-  EXPECT_EQ(blankEsm, plugin.GetName());
-  EXPECT_TRUE(plugin.GetMasters().empty());
-  if (GetParam() == GameType::openmw ||
-      GetParam() == GameType::oblivionRemastered) {
-    EXPECT_FALSE(plugin.IsMaster());
-  } else {
-    EXPECT_TRUE(plugin.IsMaster());
-  }
-  EXPECT_FALSE(plugin.IsEmpty());
-  EXPECT_EQ("5.0", plugin.GetVersion());
-
-  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw) {
-    EXPECT_FLOAT_EQ(1.2f, plugin.GetHeaderVersion().value());
-  } else if (GetParam() == GameType::tes4 ||
-             GetParam() == GameType::oblivionRemastered) {
-    EXPECT_FLOAT_EQ(0.8f, plugin.GetHeaderVersion().value());
-  } else if (GetParam() == GameType::starfield) {
-    EXPECT_FLOAT_EQ(0.96f, plugin.GetHeaderVersion().value());
-  } else {
-    EXPECT_FLOAT_EQ(0.94f, plugin.GetHeaderVersion().value());
-  }
-}
-
 TEST_P(PluginTest, loadingWholePluginShouldReadFields) {
   const auto pluginName = GetParam() == GameType::openmw
                               ? blankMasterDependentEsm
@@ -369,22 +308,6 @@ TEST_P(PluginTest, loadingWholePluginShouldReadFields) {
   }
 }
 
-TEST_P(PluginTest, loadingWholePluginShouldCalculateCrc) {
-  Plugin plugin(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, false);
-
-  EXPECT_EQ(blankEsmCrc, plugin.GetCRC());
-}
-
-TEST_P(PluginTest, loadingANonMasterPluginShouldReadTheMasterFlagAsFalse) {
-  Plugin plugin(game_.GetType(),
-                game_.GetCache(),
-                game_.DataPath() / blankMasterDependentEsp,
-                true);
-
-  EXPECT_FALSE(plugin.IsMaster());
-}
-
 TEST_P(PluginTest, loadingWholePluginShouldSucceedForOpenMWPlugins) {
   const auto omwgame = "Blank.omwgame";
   const auto omwaddon = "Blank.omwaddon";
@@ -430,66 +353,6 @@ TEST_P(
             plugin3.IsLightPlugin());
 }
 
-TEST_P(PluginTest,
-       isMediumPluginShouldBeTrueForAMediumFlaggedPluginForStarfield) {
-  if (GetParam() != GameType::starfield) {
-    auto bytes = ReadFile(dataPath / blankEsm);
-    bytes[9] = 0x4;
-    WriteFile(dataPath / blankEsm, bytes);
-  }
-
-  const auto pluginName =
-      GetParam() == GameType::starfield ? blankMediumEsm : blankEsm;
-  Plugin plugin(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / pluginName, true);
-
-  EXPECT_EQ(GetParam() == GameType::starfield, plugin.IsMediumPlugin());
-}
-
-TEST_P(PluginTest, isUpdatePluginShouldOnlyBeTrueForAStarfieldUpdatePlugin) {
-  auto bytes = ReadFile(dataPath / blankMasterDependentEsp);
-  bytes[9] = 0x2;
-  WriteFile(dataPath / blankMasterDependentEsp, bytes);
-
-  Plugin plugin1(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsp, true);
-  Plugin plugin2(game_.GetType(),
-                 game_.GetCache(),
-                 game_.DataPath() / blankMasterDependentEsp,
-                 true);
-
-  EXPECT_FALSE(plugin1.IsUpdatePlugin());
-  EXPECT_EQ(GetParam() == GameType::starfield, plugin2.IsUpdatePlugin());
-}
-
-TEST_P(PluginTest,
-       isBlueprintPluginShouldOnlyBeTrueForAStarfieldBlueprintPlugin) {
-  SetBlueprintFlag(dataPath / blankMasterDependentEsp);
-
-  Plugin plugin1(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsp, true);
-  Plugin plugin2(game_.GetType(),
-                 game_.GetCache(),
-                 game_.DataPath() / blankMasterDependentEsp,
-                 true);
-
-  EXPECT_FALSE(plugin1.IsBlueprintPlugin());
-  EXPECT_EQ(GetParam() == GameType::starfield, plugin2.IsBlueprintPlugin());
-}
-
-TEST_P(PluginTest, loadingAPluginWithMastersShouldReadThemCorrectly) {
-  Plugin plugin(game_.GetType(),
-                game_.GetCache(),
-                game_.DataPath() / blankMasterDependentEsp,
-                true);
-
-  if (GetParam() == GameType::starfield) {
-    EXPECT_EQ(std::vector<std::string>({blankFullEsm}), plugin.GetMasters());
-  } else {
-    EXPECT_EQ(std::vector<std::string>({blankEsm}), plugin.GetMasters());
-  }
-}
-
 TEST_P(PluginTest, loadingAPluginThatDoesNotExistShouldThrow) {
   try {
     Plugin(game_.GetType(),
@@ -503,125 +366,6 @@ TEST_P(PluginTest, loadingAPluginThatDoesNotExistShouldThrow) {
   }
 }
 
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveThatExactlyMatchesAnEsmFileBasenameShouldReturnTrueForAllGamesExceptMorrowindAndOblivion) {
-  bool loadsArchive =
-      Plugin(
-          game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true)
-          .LoadsArchive();
-
-  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw ||
-      GetParam() == GameType::tes4 ||
-      GetParam() == GameType::oblivionRemastered)
-    EXPECT_FALSE(loadsArchive);
-  else
-    EXPECT_TRUE(loadsArchive);
-}
-
-#ifdef _WIN32
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveThatExactlyMatchesANonAsciiEspFileBasenameShouldReturnTrueForAllGamesExceptMorrowindAndStarfield) {
-  bool loadsArchive =
-      Plugin(game_.GetType(),
-             game_.GetCache(),
-             game_.DataPath() / std::filesystem::u8path(nonAsciiEsp),
-             true)
-          .LoadsArchive();
-
-  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw ||
-      GetParam() == GameType::starfield)
-    EXPECT_FALSE(loadsArchive);
-  else
-    EXPECT_TRUE(loadsArchive);
-}
-#endif
-
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveThatExactlyMatchesAnEspFileBasenameShouldReturnTrueForAllGamesExceptMorrowind) {
-  bool loadsArchive =
-      Plugin(
-          game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsp, true)
-          .LoadsArchive();
-
-  if (GetParam() == GameType::tes3 || GetParam() == GameType::openmw)
-    EXPECT_FALSE(loadsArchive);
-  else
-    EXPECT_TRUE(loadsArchive);
-}
-
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheEsmFileBasenameShouldReturnTrueForOnlyTheFalloutGames) {
-  bool loadsArchive = Plugin(game_.GetType(),
-                             game_.GetCache(),
-                             game_.DataPath() / blankDifferentEsm,
-                             true)
-                          .LoadsArchive();
-
-  if (GetParam() == GameType::fo3 || GetParam() == GameType::fonv ||
-      GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr) {
-    EXPECT_TRUE(loadsArchive);
-  } else {
-    EXPECT_FALSE(loadsArchive);
-  }
-}
-
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheEspFileBasenameShouldReturnTrueForOnlyOblivionAndTheFalloutGames) {
-  bool loadsArchive = Plugin(game_.GetType(),
-                             game_.GetCache(),
-                             game_.DataPath() / blankDifferentEsp,
-                             true)
-                          .LoadsArchive();
-
-  if (GetParam() == GameType::tes4 || GetParam() == GameType::fo3 ||
-      GetParam() == GameType::fonv || GetParam() == GameType::fo4 ||
-      GetParam() == GameType::fo4vr ||
-      GetParam() == GameType::oblivionRemastered) {
-    EXPECT_TRUE(loadsArchive);
-  } else {
-    EXPECT_FALSE(loadsArchive);
-  }
-}
-
-#ifdef _WIN32
-TEST_P(
-    PluginTest,
-    loadsArchiveForAnArchiveWithAFilenameWhichStartsWithTheNonAsciiEspFileBasenameShouldReturnTrueForOnlyOblivionAndTheFalloutGames) {
-  bool loadsArchive =
-      Plugin(game_.GetType(),
-             game_.GetCache(),
-             game_.DataPath() / std::filesystem::u8path(otherNonAsciiEsp),
-             true)
-          .LoadsArchive();
-
-  if (GetParam() == GameType::tes4 || GetParam() == GameType::fo3 ||
-      GetParam() == GameType::fonv || GetParam() == GameType::fo4 ||
-      GetParam() == GameType::fo4vr ||
-      GetParam() == GameType::oblivionRemastered) {
-    EXPECT_TRUE(loadsArchive);
-  } else {
-    EXPECT_FALSE(loadsArchive);
-  }
-}
-#endif
-
-TEST_P(PluginTest,
-       loadsArchiveShouldReturnFalseForAPluginThatDoesNotLoadAnArchive) {
-  const auto pluginName = GetParam() == GameType::starfield
-                              ? blankDifferentEsp
-                              : blankDifferentMasterDependentEsp;
-  EXPECT_FALSE(Plugin(game_.GetType(),
-                      game_.GetCache(),
-                      game_.DataPath() / pluginName,
-                      true)
-                   .LoadsArchive());
-}
-
 TEST_P(PluginTest, isValidShouldReturnTrueForAValidPlugin) {
   EXPECT_TRUE(Plugin::IsValid(game_.GetType(), game_.DataPath() / blankEsm));
 }
@@ -655,138 +399,6 @@ TEST_P(PluginTest, isValidShouldReturnTrueForAnOpenMWOmwscriptsFile) {
   }
 }
 
-TEST_P(
-    PluginTest,
-    isValidAsLightPluginShouldReturnTrueOnlyForASkyrimSEOrFallout4PluginWithNewFormIdsBetween0x800And0xFFFInclusive) {
-  bool valid =
-      Plugin(
-          game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true)
-          .IsValidAsLightPlugin();
-  if (GetParam() == GameType::fo4 || GetParam() == GameType::fo4vr ||
-      GetParam() == GameType::tes5se || GetParam() == GameType::tes5vr ||
-      GetParam() == GameType::starfield) {
-    EXPECT_TRUE(valid);
-  } else {
-    EXPECT_FALSE(valid);
-  }
-}
-
-TEST_P(
-    PluginTest,
-    isValidAsMediumPluginShouldReturnTrueOnlyForAStarfieldPluginWithNewFormIdsBetween0And0xFFFFInclusive) {
-  bool valid =
-      Plugin(game_.GetType(), game_.GetCache(), dataPath / blankEsm, true)
-          .IsValidAsMediumPlugin();
-  if (GetParam() == GameType::starfield) {
-    EXPECT_TRUE(valid);
-  } else {
-    EXPECT_FALSE(valid);
-  }
-}
-
-TEST_P(
-    PluginTest,
-    IsValidAsUpdatePluginShouldOnlyReturnTrueForAStarfieldPluginWithNoNewRecords) {
-  const auto sourcePluginName =
-      GetParam() == GameType::starfield ? blankFullEsm : blankEsp;
-  const auto updatePluginName = GetParam() == GameType::starfield
-                                    ? blankMasterDependentEsp
-                                    : blankDifferentPluginDependentEsp;
-
-  std::vector<Plugin> plugins;
-  plugins.push_back(Plugin(game_.GetType(),
-                           game_.GetCache(),
-                           game_.DataPath() / sourcePluginName,
-                           false));
-  plugins.push_back(Plugin(game_.GetType(),
-                           game_.GetCache(),
-                           game_.DataPath() / updatePluginName,
-                           false));
-
-  if (GetParam() == GameType::starfield) {
-    const auto pluginsMetadata =
-        Plugin::GetPluginsMetadata({&plugins[0], &plugins[1]});
-    plugins[1].ResolveRecordIds(pluginsMetadata.get());
-
-    plugins[0].ResolveRecordIds(nullptr);
-    plugins[1].ResolveRecordIds(nullptr);
-  }
-
-  EXPECT_FALSE(plugins[0].IsValidAsUpdatePlugin());
-  EXPECT_EQ(GetParam() == GameType::starfield,
-            plugins[1].IsValidAsUpdatePlugin());
-}
-
-TEST_P(PluginTest,
-       doRecordsOverlapShouldReturnFalseIfTheArgumentIsNotAPluginObject) {
-  Plugin plugin1(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, false);
-  TestPlugin plugin2;
-
-  EXPECT_FALSE(plugin1.DoRecordsOverlap(plugin2));
-}
-
-TEST_P(PluginTest,
-       doRecordsOverlapShouldReturnFalseForTwoPluginsWithOnlyHeadersLoaded) {
-  Plugin plugin1(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, true);
-
-  const auto pluginName = GetParam() == GameType::openmw
-                              ? blankMasterDependentEsm
-                              : blankMasterDependentEsm + ".ghost";
-  Plugin plugin2(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / pluginName, true);
-
-  EXPECT_FALSE(plugin1.DoRecordsOverlap(plugin2));
-  EXPECT_FALSE(plugin2.DoRecordsOverlap(plugin1));
-}
-
-TEST_P(PluginTest,
-       doRecordsOverlapShouldReturnFalseIfThePluginsHaveUnrelatedRecords) {
-  Plugin plugin1(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsm, false);
-  Plugin plugin2(
-      game_.GetType(), game_.GetCache(), game_.DataPath() / blankEsp, false);
-
-  if (GetParam() == GameType::starfield) {
-    plugin1.ResolveRecordIds(nullptr);
-    plugin2.ResolveRecordIds(nullptr);
-  }
-
-  EXPECT_FALSE(plugin1.DoRecordsOverlap(plugin2));
-  EXPECT_FALSE(plugin2.DoRecordsOverlap(plugin1));
-}
-
-TEST_P(PluginTest,
-       doRecordsOverlapShouldReturnTrueIfOnePluginOverridesTheOthersRecords) {
-  const auto plugin1Name =
-      GetParam() == GameType::starfield ? blankFullEsm : blankEsm;
-  const auto plugin2Name = GetParam() == GameType::openmw
-                               ? blankMasterDependentEsm
-                               : blankMasterDependentEsm + ".ghost";
-
-  std::vector<Plugin> plugins;
-  plugins.push_back(Plugin(game_.GetType(),
-                           game_.GetCache(),
-                           game_.DataPath() / plugin1Name,
-                           false));
-  plugins.push_back(Plugin(game_.GetType(),
-                           game_.GetCache(),
-                           game_.DataPath() / plugin2Name,
-                           false));
-
-  if (GetParam() == GameType::starfield) {
-    plugins[0].ResolveRecordIds(nullptr);
-
-    const auto pluginsMetadata =
-        Plugin::GetPluginsMetadata({&plugins[0], &plugins[1]});
-    plugins[1].ResolveRecordIds(pluginsMetadata.get());
-  }
-
-  EXPECT_TRUE(plugins[0].DoRecordsOverlap(plugins[1]));
-  EXPECT_TRUE(plugins[1].DoRecordsOverlap(plugins[0]));
-}
-
 TEST_P(PluginTest,
        getAssetCountShouldReturnNumberOfFilesInArchivesLoadedByPlugin) {
   const auto assetCount =