I know leaks don't normally come around like this, but my insider person was at a very large internal idea generation event with Gamefreak, TPC, TPCI Nintendo, ILCA, and many other companies' employees talking about pokemon games in the future. Next to none of this is confirmed but I still thought sharing these ideas would be interesting. I am not normally keeping up with news about Pokemon but was a fan over ten years ago, if I remember correctly, and only got "reminded" of it when Dexit was made known.

What I know for sure ISN'T an idea, but rather the plan, is this:
The next new region won't be coming next year. Internally, PLZA is considered a larger project than normal, introducing mons and mechanics. SV still has a remaining update of some kind. There will also be an update for PLZA, although I don't know what is in it, just that it was mentioned that it exists. These have too much invested into them at this point and need to drop. Gen 10 will happen in 2026, with DLC in 2027. The "idea" they're throwing around is whether or not to merge these DLCs or have it like Gen 8's and 9's.
Idea time: Tentatively, most people there want a Johto Remake before Gen 10, and for them to feature Raikou and Entei. You might be thinking Let's Go, but I don't have any info on what type of game it is, just that it's being planned for.
Gen 10 is planned for 2026, and DLC was barely discussed. What was discussed was Unova coming after, and these have the most conflicting and craziest ideas yet. I'll remind you that these aren't confirmed, but they're debating between having BW and BW2 come in one game, but have multiple games in one, or splitting up the releases.
I'll continue below