>>57858824They probably won't, don't go expecting anything like that.
The only time since DP's dev hell that they've even come close to announcing a new gen before the current year's game has released is when they said that a new gen was being made for switch literally 1 week after the reveal of LGPE.
Admittedly, this was likely because the reaction to LGPE was lukewarm at best, and it is the only thing that makes what you suggest possible. However, given how fucking wacky Switch 2 stuff has been handled, with with even big media outlets like IGN not getting consoles to review before launch and a day 1 patch required to make the console function, I wouldn't be surprised if Ninty is pressuring GF/TPCi to keep things quiet so they have greater control over what is being pushed at what time. They're going a really weird controlling phase, so I wouldn't be surprised if first party and Pokémon games are marketed a little differently.