Not sure. I'd definitely want to come back to this wonderful reality we call Earth. If I were to visit the Pokemon world for a long-term stay... what would it be like though? Would the reality be similar to that of the games or the television series; innocent and unknowing? Or would my very presence trigger corruption and change in that existential plane? That is to say, would I be able to do stuff like: murder, fornicate, curse, etc, and how would it affect the world around me? I've often related on this matter in my leisure... there are many loopholes and paradoxes that could occur, due to rules of our reality being broken, if a being of our conscience were to step into the reality of a child-themed entertainment world.
That said, would I be able to bring a companion from this world? I say, I might go insane after a while in such a place with no remnant of a sensical universe but myself. Solipsism would soon set in. Yes, a companion would be essential.
And then, would I really want to stay forever? There are so many things of this world that I love and care for. Another thing to consider: would I be able to bring back souvenirs, or rather the pokemon I encountered in my travels?
Anyways, there is a lot to consider. I think this fantasy is best kept just that... a fantasy. With that, I leave you. Good night, sleep tight, I'm going to the pokemon world.