GeorgeRRFartin according to the forum threads i read, these all pull the data from IGDB, so to include games that aren’t on there you have to manually make an IGDB post for them yourself and wait for it to be approved, otherwise they show up as “unknown game”, not even listing the filename. depending on how many people have done that, I guess it wouldn’t be too much on an issue. i’ll try it out!
update: it was a bit fiddly to install but i figured it out. about half the itch.io games associated with my account are listed as “unknown game”. that’s not great. still, feels nice to have most of the games i want to check out soon in one clean showcase