Consider the reveal trailer, it would most likely be Mario Kart but I don't rule out a Zelda remaster either. Too bad it wouldn't be Metroid Prime 4 since it already annouced for Switch and Switch 2 is BC so no reason to port it. I hope there is a surprise title that they still hold back because Mario Kart seem like a rather boring choice for launch title consider it barely look any different than Mario Kart 8.