Moscow has 12.7 million people easy to get lost in the rabble. Since Russian police won’t detain a US citizen for a domestic warrant why hide at all. Just don’t get busted for breaking Russian law and apply for a 3 year multiple renewable personal visa. You can’t work in Russia officially at least but the Moscow black economy is the stuff legend is made of. Plus in the post covid world anywhere with broadband access is viable work environment for any number of fields of technical , intellectual or artistic work take payment via the Bahamas, Cayman Islands or Switzerland never deal with Russia or USA gmen.
There’s a dude, something of right wing internet lore, who is a person non gratis because of his politics. He’s a hacker of sorts. Anyhow, he can’t come back to the US and bounces around Eastern Europe. I haven’t seen him on the internet for a while but I am sure he’s out there somewhere.