Sorry if the title wasn't very descriptive.
So, I have Pokèmon White and White 2, and haven't been playing much...because I'm kinda bored for now. But my cousin has a friend(who I met) who has Pokèmon Black and White 2(and a 3DS), and we got all excited because we could battle and stuff. Sadly, I didn't get my DSi to my cousin's house, so we couldn't do anything anyways.
Next time I go, I'll get my DSi and games too, but now that I think about it, what all can we both do, aside from trade version-exclusive Pokèmon and battle each other?