It’s extremely unpopular on mumsnet, so I expect you’ll get a lot of things to think about and you should consider carefully on the negative side, OP.
We adopted a dog from the Balkans. She’s wonderful. Obviously had a home once before, knew all her commands, house trained etc. Her only vice is occasional food-stealing if left to her own devices with something tempting - but she’s part Lab so I think that’s par for the course. And she’s squirrel obsessed. Otherwise she is very calm, kind, good with cats and kids and other dogs, whom she mostly ignores.
The rescue we used does home checks via UK networks (e.g. our checker also worked for RSPCA), has some UK fosterers so limited UK back up - but they do a lot of matching to make sure placements aren’t likely to fail. We saw videos of our dog interacting with cats and kids. They neuter/spay and make sure all injections are done, and test for basically everything so there’s no risk of transporting disease. The descriptions of their dogs on their FB page are comprehensive.
They said that contrary to what people believe, a lot of ‘street dogs’ in the Balkans haven’t been born and brought up as strays but are usually pet dogs about 9 months to 2 years (the tricky teenage stage for lots of dogs) whose owners just dump when they’re no longer cute puppies, or dogs bought e.g. for training to hunt who are not up to the grade, or pets whose owners just abandon them when circumstances change. There’s no penalties against that, and then the authorities just round them up to kill. It’s not to say they won’t have problems, just that a lot of them will have lived in homes before or have been trained and not be the terrified feral dogs you might imagine.
We tried UK rescues but cats & kids ruled out a lot of options, and my husband’s preference for type of dog ruled out what was left - he was adamant no Staffy type or similar (though I love them). I really wanted to rescue and didn’t want a puppy.
Negatives are you cannot meet the dog first (although there are some overseas rescues that have dogs in UK foster homes) so you’re committed before you’ve even seen the dog in person; you will need to expect to dedicate time to training and be alert for potential issues; your family will all need to understand that your dog needs particular calm and gentle behaviour at least until you all know each other; you will be judged by MN for bringing a dog from abroad!
I think if the charity you use is legit and does all it can to rehome healthy dogs matched by personality to homes they will thrive in, then it’s fine. Choose wisely, if anything gives you pause then just don’t go ahead. Due diligence, ask every question you need to. They should expect that and be happy to answer honestly with good and bad points about the dogs they have.