itch.io

(Trademarked! The word you're looking for is "trademarked," not "copyrighted" — people mix the two concepts up all the time and it is apparently my mission, for some reason, to make this clear)

You probably mean trademarked (as only works are under copyright, not an English term) and it doesn't look like it (at least not in the US and game category see https://tmsearch.uspto.gov/) Only the specific Gundam game titles and logos are trademarked.