I bring bad and good news.
Tested on Kingdom Hearts Birth By Sleep Final Mix.
The bad:
The VS Mode, Arena and Command modes don't work, and appear to work shortly for only one player if he's hosting on JPCSP and the other player is on PPSSPP.
The good:
Race Mode works. It's the only mode that works in this game. Tested with JPCSP(host) to PPSSPP(player).
Testers: me, Headbanguer666 and Zinx777.
Tested on Kingdom Hearts Birth By Sleep Final Mix.
The bad:
The VS Mode, Arena and Command modes don't work, and appear to work shortly for only one player if he's hosting on JPCSP and the other player is on PPSSPP.
The good:
Race Mode works. It's the only mode that works in this game. Tested with JPCSP(host) to PPSSPP(player).
Testers: me, Headbanguer666 and Zinx777.