No I meant MY JOKE was in poor taste LOL, anyways let's drop this
If you open your game in a hex editor and change the Title ID slightly, you will be able to accomplish this. For example, You have GXXE01 as the title ID for Pokemon XD, for Pokemon XG you could set the title ID to GXXE02 I believe, and you'd be fine. I did the opposite of this actually, the Super Mario Sunshine Multiplayer mod was using a separate save file from single player because its title ID was GSME02, so I changed it to GSME01.