1) Given that he isn't really human, or alive even, but more of a pseudo-god entity, I don't think he would gain the need within that framework.

2) Yeah, I mean, it is possible for it to be a property of the worlds that they forcibly adjust his frequency to that world. So like, he'd be able to move between that world's planes or something, just not go between worlds. Idk, something like that could work.