So far we have Venezuela proposing the petro. Russia is proposing their own. I know Estonia is very crypto and tech friendly.
Petro and other state shitcoins are not cryptocurrencies, they are completely centralized state-owned electronic money, and you are very naive to think that any government in the world would create something truly decentralized.
As for which country would recognize cryptocurrencies as legal tender, by bet is on Switzerland, as it seems to be the most libertarian country in the world. The other possibility is if some third-world country would do this as part of the plan for rapid economic development based on transparency and openness.