EA’s SSX 3 has a communication feature between the console and handheld versions. When connected with a GC-to-GBA link cable, players can freely transfer funds back and forth between the Gamecube and Gameboy Advance versions.
In other words, if you want to grind the console version to easily max out stats in the GBA version, you can do that. And vice versa. Just remember, funds are assigned to each character. So you cannot transfer cash from Character A to Character B.