Durmstrang's whole situation is weird, but I think it would be a better fit for a hockey HP AU. It's actually in a region that a lot of hockey players come from, and we know it also accepts students from as far as Bulgaria, so it would make sense for Russian students to attend. (I can't remember if there were any non-Brits at Hogwarts at all, but that could be my memory.)

But since we know very little about Durmstrang, using it as a setting wouldn't be too different from inventing a school from whole cloth anyway.