Your comment made me think: There is a “cross references” section on IFDB pages. Maybe it would be nice to add “inspired by” to the list of options there?
I made a comment there asking what the reverse direction would be called.
What would we want the toname to be? e.g. if game X inspires Y, we’d say that Y is “inspired by” X, and that X “inspired” Y?
These cross references show up in the “Game Details” section, so, for example, on Counterfeit Monkey, it might say “Inspired by Leather Goddesses of Phobos,” and on LGoP it might just say “Inspired Counterfeit Monkey”.
I wonder if “Inspired Counterfeit Monkey” is clear enough out of context, especially without any preposition.