serverless-webpack/examples/babel-webpack-4

This is the default babel webpack-4 example to look at, because only dynamic entry point resolution lets you use Serverless completely. Individual packaging with a per-function dependency optimization is only available with that approach.

You can also try to invoke a function locally:

serverless invoke local --function=first --path=./event.json

Also it has a .vscode/launch.json file for debugging the functions using vscode.