Ia that impossible. What is the differnce between Pokemon bank and Transporter? DId I dream this you can get thouse Pokemon of any X and Y games?
Pokémon X and Y are so far the only games (excluding B/W and B/W2) in the franchise where you can't catch the trademark legendary of the other game.
Zygarde is available in both games however.
You can't catch both on one game, but you can trade them over to one game.