An interesting exploit has been discovered by Twitter user @JarylGaren (photo and info courtesy of him) which allows you to view 3DS and Wii U games on the Switch eShop. Simply adding a game to your wishlist via Nintendo's official website will allow you to view any game listing directly on the Switch's digital store, regardless of the platform. While some titles fail to load any images, certain ones like Super Mario 3D World, Pikmin 3, and Paper Mario Color Splash have a fully functional eShop page.
This has lead to some folks sharing photos as an act to create rumors. While the photos themselves are actually real, there is no actual evidence or official announcement that any of these games will be coming to Switch. At least not yet!
Switch ports of Pikmin 3 and Super Mario 3D World have been discussed for quite some time now, with some potentially legitimate rumors being shared by VGC and VentureBeat. Hopefully Nintendo has something official to share soon!