Like all of those PS2/GameCube era licensed games of like Rattatouille, etc. where the genre changes every chapter or so. It's essentially a collection of mini-games or half-baked games and doesn't have a fixed genre necessarily. Games like Sonic Adventure and the post-N64 James Bond games are kinda' like that too.
Is there not a term for this?
Games where the devs threw a bunch of ideas into a bucket and put them all in the game for padding because they had 8 months to finish. Also the game is made from the corpses of 10 other incomplete projects
It Takes Two actually did the level-by-level genre flip extremely well recently
Variety games?
Most games based on movies are platformers like Super Mario Bros. I'm not familiar with Ratatouille but wikipedia calls it a platform game and the gameplay video I just watched seems to confirm (although it appears there may be a rhythm based minigame within).