Usually, when Nintendo has a first-party game releasing on the Switch very soon. they open up an official site for the game. Sometimes, these sites contain lots of info about the game, some of which could be new. Most of the time, however, they’re just teaser sites that don’t have anything new.
In this case, it is unfortunately the latter. The official site for Super Mario 3D World + Bowser’s Fury opened to the public earlier today, but it is just a teaser site that only contains info previously revealed, Super Mario 3D World + Bowser’s Fury releases exclusively on the Switch on February 12th.