I have no clue how pokemon bank worked in the first place but will all Pokemon from this game be able to transfer to X/Y do you think?
Because you couldn't use Download Play with a 3DS game using a DS since you can't play a 3DS game on a DS. They had to use a 3DS app to be able to communicate with the DS games, which has been proven possible by Pokémon Dream Radar. (This is really just my guess, by the way.)
As for transferring... do you mean between OR/AS and X/Y via Bank or trading?
I'd be surprised if that wouldn't be possible.