Pokémon Bank was updated late today and now supports Pokémon Sun and Pokémon Moon, making it easy to transfer Pokémon from multiple copies of Pokémon Sun and Pokémon Moon — including the downloadable versions — to a single game!
Also updated is the ability to transfer Pokémon you’ve caught in the Nintendo 3DS Virtual Console versions of Pokémon Red, Pokémon Blue, and Pokémon Yellow into your Sun or Moon. Pokémon from Pokémon Omega Ruby, Pokémon Alpha Sapphire, Pokémon X, and Pokémon Y can also be brought into Pokémon Sun and Pokémon Moon in the same way.