I switched to Dvorak after I got RSI about 10 years ago. It was so bad that I couldn't type anymore. So I taught myself Dvorak because I did some research and it seemed it could have been helpful. I was pretty desperate to solve my problem, and it seemed Dvorak could help since your hands travel less than Qwerty.

Fortunately, I haven't had RSI ever since I switched to Dvorak.

Switching to Dvorak is quite tedious, and I wouldn't recommend it unless you have a good reason to do so.

Regarding internationalization, I write in English, Spanish and Italian in Dvorak with no problem. It really doesn't any difference to me as compared to Qwerty.