I think we get the summer announcement of the Switch 2 and then the March 2025 release, which makes the most sense, same time frame as the original Switch, and this would also lead to Pokemon Legends Z-A releasing on Switch and as a Switch 2 launch title. They don't have anything of note announced for the Switch for later this year, though they could still have something planned to announce within the next few months to have ready for this holiday season, but that there's nothing announced makes me think that's a good sign of prepping for the next gen.
I am going to say that it'll be backwards compatible, I think unless Nintendo is planning to do a drastically different method of physical media, something I don't even know what that could be, they'll keep the same media setup, so it can play Switch games, or play what will be higher storage Switch 2 carts. Honestly, I'm gonna be pretty disappointed if it's not backwards compatible, that's kinda the only feature I care about with this. I think for launch alongside Pokemon Legends, we would need to see something pretty impactful that is like THE Switch 2 launch release, and I think something like Metroid Prime 4 could be that. That's been a game in development hell for so long, but that would be a big deal to have right out of the gate.
That's all of what I'd say for a launch window, to hard to guess what kind of games they will go for, though my one hope would be a new top down Zelda, not a remake, not in that lame Link's Awakening style, and actually letting a third party company handle it, like Capcom did in the past, or Cadence of Hyrule more recently, so we get a Zelda with some fresh eyes on the series. That would honestly be something to get me super excited that's out of left field.