The current overlay repo picks up the latest compatible released commit for a plugin also if it contains multiple packages.

That might work in most cases, but actually the npm packages (the releases on npm) are not necessarily based on the same commit.

Example

There is an "example-plugin" has a frontend and a backend plugin/package..

1. Commit changes the frontend plugin
2. Plugin owner release the frontend and backend
3. Commit B changes the frontend plugin
4. Commit C changes the backend plugin
5. Plugin owner decides to just release the backend

The overlay repository has at the moment just the option to build the frontend and backend plugin together from Commit A or commit.

Actually what is needed is that the overlay repo has an option to release the frontend plugin from commit A and the backend plugin from commit C.

In the Backstage community plugin repo and rhdh-plugins repo this might not be possible because an author "can not" (when following the changeset rules) decide to release the backend without releasing the frontend when there is a changeset in commit B. But other repos might work different.