/vp/ help me out. My Newphew was robbed and he lost his 3ds all his pokemon games. He had a full national pokedex. I want to suprise him with a belated christmas gift and give him access to all the pokemon gens again.

If I bought AlphaSapphire. SoulSilver, White and White 2, and Pokemon Y would that allow access to every gen? Do I need to buy anything else and can Pokemon be traded freely between all those games? I know I would also need to pay for Pokemon bank on top of that but I just wanna make sure I get this right the first time before I surprise him.