You can still play online multiplayer games. Smash Bros, Mario Kart 7, Monster Hunter Stories PvP etc. The whole Pokemon Bank also works. They only removed the

You can still play online multiplayer games. Smash Bros, Mario Kart 7, Monster Hunter Stories PvP etc. The whole Pokemon Bank also works. They only removed the option in eShop to purchase new games, you can still also download everything you bought before.