This. It can be hard to move to a different country.
My best advice is if you are of European ancestry look into whatever country your ancestors came from. I’m qualified to move to two different countries just based on the fact that my grandparents were born there. It makes it a heck of a lot easier to move.
If I had my choice and I was moving for horse reasons, I’d do France, the Netherlands, or Ireland, in that order.
However, because of the relative closeness of all EU countries, pretty much all of them have a wealth of horse activities.
Pretty much every European country has English as a requirement in the school system, so most people under about 30-40 will speak English. The country and how rural you are will determine how much English they actually speak. But no matter what, plan on taking intensive language classes so you speak their language.
Often overlooked and closer to home are Canada, Mexico, and Brazil. Canada will obviously be not too much different than the US (in customs and language) but you’d still have access to the USA shows if you don’t want to give those up.
Mexico and Brazil have become more and more popular with expats and I do know of a few people who moved down permanently with their horses and love it. Cost of living is very cheap, and from what I understand there’s a big horse show scene in both countries. However, one of them has an armed guard on the property; she’s had some minor issues with theft (Brazil. Though she does say she loves it there and 99% of the time it’s safe, clean, and fun. It’s just that 1% that she doesn’t trust.)
Another thing to think about is what language you can pick up the easiest. I took 2 years of Spanish and French. I can speak elementary school level French, but I could never pick up Spanish. I actually understand a lot of the language, but when I try to speak it, it comes out as complete nonsense. So for me, anywhere that speaks Spanish would be out.