The problem of going to Russia as a soldier

Russian citizenship is not required. Conscription is generally nothing more than physical fitness test and political review. Every country is similar, as long as it is passed. You can apply for Russian citizenship after serving in the army for one year, but non-Russians can't join the elite troops.

As for Russia, there are actually foreign legions, but they are all civilians from the former Soviet Union countries who volunteered to join the army, which has nothing to do with China people.