Hi, i was searching a way to start my Pokémon white 2 adventure in challenge mode. I have an old 3dsxl with CW and twilight menu. So i decided to download a rom of black 2 and enable the cheat to unlock the key system, and then transfer them into my white 2 cartridge. But even the key exchange won't work even if i place my 2 3ds in front of each other. Did I do something weong, is there another way to do it, or it is simply impossible and I necessarily need to have a real black 2 cartridge with the keys unlocked?