Neat, it’s Lumiose City! Hopefully this is the post-patch version. I’m not sure if this is a 3DS-exclusive stage for the new Smash Bros., but the game’s director Masahiro Sakurai did provide this comment on the level: “The Prism Tower rises above Lumiose City. Up until a few seconds ago, the fighters were brawling on top of that tower.”
This Animal Crossing: New Leaf stage, though, is 3DS-only (the Wii U version has City Folk’s Smashville). Sakurai offered these details on Tortimer Island: “On this stage, fighters are randomly placed on a different island layout every time they visit.” Hopefully they cleared all the wharf roaches.