In our team we use eslint with a bunch of projects. Naturally we want to use the same eslint configuration in our projects. To do that we have created a separate package with the shared .eslintrc. We include it as dev dependency in our projects and pass its .eslintrc on the command line via -c option.
This works but then we found that we cannot use local .eslintrc files to extend/override the shared configuration.
Now I have found Shareable Configs which is a great idea. Unfortunately it requires that "the module name begins with eslint-config-". This seems rather restrictive. To use it, we would have to rename our package with shared config, which would be a breaking change.

Why not make this an optional prefix?
For example if we have

extends: xyz

Then search for package:

1. eslint-config-xyz
2. xyz