There' no space in the maps. Plus I don' think you would be able to collect resources since pokemon are the tools.
If they recoded the items to something you cannot obtain like a dragon's breath potion and add a secondary world purely for survival, it would be possible However the amount of effort and dev time that it would require probably wouldn't make it worth their time lol.
Pokeworld is Pokemon, with other side Pokemon features like Pokemon Skyblock, Pokemon Murder Mystery (Even though there is no Mystery, RUN FROM THE GASTLY, HAUNTER, OH SHOT THERE IS A GENGAR, TOO.), PokeWars (Pokemon + Bed Wars). Battle Royale is the only game mode that isn't Pokemon Related.
There is a pretty big difference between an SMP and a skyblock. Honestly I flat hate skyblock and I love smps lol. Either way, as plausible as it might be, highly doubtful it would ever happen.
I see what your trying to say and maybe it could work, but I would like to keep pokeworld about pokes, not building houses