I'm sure some of our stuff has found its way into the game, but they also seem to have expanded it to 33 teams, and the menu has a mysterious extra entry at the bottom (the scroll arrow remains even though you're at what is normally the bottom item). So they've definitely done some work. The player portraits don't match one of the 2020 ROMs I looked at recently, so I think they used their own pictures (however I didn't check the other ROM)