I was looking at the Handbook localization chapter yesterday. It appears to be out of date. However, I'm a monolingual American and have never had to deal with any of that. So it's hard to know what needs to be done.
There is a section about Russian at the end of that chapter, and only some links for other languages. I would like to update that, but need help with it. My experience is that adapting existing documents to the Handbook format is usually more work than just writing them from scratch. But they can be used as a guideline.