You are describing the EXACT plugin I am after. Please shout if you need any help testing it. (Or writing it if I can find time)
They are added as separate releases, but MB style guideline does not allow them to be named fully.
There are many deluxe editions added to the database where someone then comes along and decides that “deluxe” is ETI and they remove that from the title and put it in the disambuguration text instead. So the Deluxe has its own Release correctly listed, but the title has been trimmed by an editor who doesn’t like ETI.
Here is an example: https://musicbrainz.org/release-group/27abe769-5946-4d46-938b-1937efa604a6
Look at the first two releases. I own that deluxe edition in its nice book. And it has extras added on the second disk. I also have a copy of the standard single CD edition. Currently in KODI they are titled the same.
THIS is where I would be real nice to be able to have an exceptions list that Picard can work with. If it spots that Release MBID then swap in my own chosen title of Resistance is Futile (deluxe) instead of the one Picard wants to set.