Given that Pokemon characters are prolific, I should think “original character from an existing IP” is generally allowed. In Pokemon’s case, Ash or Detective Pikachu wouldn’t be allowed, but original pikachu characters are fine.
The rules only prohibit canon characters and say nothing about locations.
But as a non-admin non-rules-setting person whose intuition is not fact, my intuition says a specific canon location like Lumiose City or Bikini Bottom wouldn’t be allowed. That said, I’m pretty sure you could have, say, Speedo City that’s very much like Bikini Bottom but doesn’t have anything canon in it.