Were you able to visit the area before you moved the category? Are you able to visit the actual area now? Was it just that you were redirected to an invalid URL after the move was completed?
In my tests on XenForo, I have not been able to reproduce any redirection problem when moving single pages or multiple pages, both in and out of areas called Tëbäa or Tébäa, even when the moved pages also had names with special characters like categorieën.