I think they avoid using actual place names for a reason. Belle isn’t mentioned to be French. Lancelot said he comes from a Kingdom, didn’t say United Kingdom. Also you kind of argue against your own point.
if we ever see her backstory, her land will look very medieval China, but it won’t be CHINA
You’re right, so even though Frankie’s world looks like Tranyslyvania it’s not and I doubt it will ever be called that. If we ever see Lancelot’s kingdom they will probably throw in some dated British stereotype, like the accent that no one actually speaks in, or bad teeth etc, but it won’t be Britian and will never be called Britain. (Camelot maybe, but they won’t mention where it is)