>>44246697My friend and I theorized a way this could work a while ago:
Make a post-game mini region. (Could even just use Pasio from Masters)
Player picks a region to start in, and plays like normal, but without an evil team side plot, just gyms and battles.
After completing one region, you go to the post-game island, which is where battle facilities are found.
From here you can go to any other region, but when you leave, you can't bring any pokemon to a new region until you are the champion there, then return to the island and repeat.
If they wanted to go full on MMO, the champion's island could have trainers running around like in Swsh.
Could even record the teams of the top trainers in the world, then have them controlled by AI to be an island E4 and champion.
This is kind of similar to PokeMMO and Masters, but I didn't know about those at the time.