Displays will be fine. You'll need a screen reader which is able to output Russian Braille, however, and that's a topic I know less about. The physical devices are identical regardless.

Yes. I am nearly fluent in Russian so can answer this. All of the major screen readers either support Russian directly, or have downloadable voices for Russian. Both windows and Apple products have Russian braille tables available, so if you have a braille display, you can output Russian. Braille displays with standalone note taking features like Hims also have Russian available. Let me know if I can help more directly.

If the localisation supports Russian, yes. Most displays should though. Which one do you have in mind?

Yes.