GC AR is blocked on the Wii, but there is an AR Loader homebrew app I think. Can't remember if that's the exact name or not. Alternatively, I think there's a modified version of Gecko OS which can use cheats in GC games. In both cases, you need to install a patched MIOS I think (which isn't really supported here, as most patched versions of MIOS can be used for GC warez as well).