I would love for China's GP event to be hosted by another Asian country, but unless South Korea picks it up, who else would have the infrastructure? I know Kazakhstan wanted to host the Olympics, and they have the Denis Ten Memorial, so maybe there? But I think it's more realistic that both the Russia and China replacements will be in Europe. I would have suggested Australia, but they're already hosting 4CC a few months later.
So I'm predicting Tallinn for sure. I'd say maybe Italy again, but they're hosting the GPF. Germany was a regular GP host in the late 90s, early 00s, so they could be a good choice.
They could also do some JGP locations (if not Kazakhstan or South Korea). Aside from the regulars, and those mentioned above, in the last 5 years the JGP has also been in Austria, Poland, Slovakia, Slovenia, Czechia, Hungary, Uzbekistan, Latvia, Croatia, Armenia, Lithuania, Belarus...