Well there is something in the bible about cursed is he who moves boundary stones, or something like that.
I know that when Russia went in, they tried to make it look as “good guy” as they could muster their grumpy bear selves to be. That they were saving that poor Crimea from that dastardly Ukraine and look it was cram full of Russians anyhow so who should complain about it?
Some kind of purchase might make sense. This, less so.
Crimea was stolen from Russia 50 years ago and given to the Ukraine. Would you want your State to be given to Canada? Would you like to vote later to return to the US only to see Mexico bitching that you did?