It works on a per-game basis, I testes shared saves on P4G and FFX (ps3 public save to my vita).
I've yet to play Odin's Sphere so I can't test this myself but the reason it's a per-game basis is because some games have extra protection on their saves.
You just need to open the game with the molecule patch and extract/import the save data. (that's assuming there is no added protection for this game)