Different schools for different sites
Have the US site based around Ilvermorny, the UK one (if it happens) based around Hogwarts, the Dutch one perhaps based around Durmstrang, the EU one based around Beauxbatons, and so on... I understand that this could be difficult as not much is widely known about all these different schools, but if we have found out enough about Hogwarts to create an entire game, then surely by digging deep enough we can find out enough about these other schools, and I am sure the people who currently use these sites are creative enough to fill in the gaps for, say, the Durmstrang equivalent of Diagon Alley, etc.
Perhaps if having the schools based around the geographical location of the URL is too difficult, we could have options when you enter the site for which school you want to attend, and have a giant chat group for everyone there, or something like that. This idea is of course up to adaptation, as are all others, it was just something that was discussed with the opening of the US site, as to whether the US site would be established as Hogwarts or Ilvermorny, and now that we have the chance to discuss the possibilities with higher ranking people, it could be a good opportunity to bring it up.
Answer
The main problem I think you would have here is the Hogwarts site being more popular than many of the others, as well as people being upset that the sites are already very firmly based as Hogwarts.
The problem is that we don't know enough about the other schools/geographic placement, to be able to make a whole univsers.
Hogwarts/diagon-alley/hogsmeade/UK is what the 7 books are about. Yes, we do hear about Bauxbatons and Durmstrang, but not nearly enough to be able make an immersive universe.
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The problem is that we don't know enough about the other schools/geographic placement, to be able to make a whole univsers.
Hogwarts/diagon-alley/hogsmeade/UK is what the 7 books are about. Yes, we do hear about Bauxbatons and Durmstrang, but not nearly enough to be able make an immersive universe.