Drone

So pardon me for any inconsistency of pokegen, or even pokemon in general. Going from Blue & Gold on GBC to Black. If anyone can help me clarify my questions, it is deeply appreciated. This will make legal pokemon in pokemon black/white? Can you make all the previous pkmn generations on black? To get event pokemon from prev gen, are they legal if you save them onto black or must they be transfered? Gameplan: I want the pokemon to have the levels and stats as if they were caught in wild.