While I don't claim to have researched this issue in depth and it's worth taking this with a pinch of salt, I'm yet to see any evidence of this, nor has it been a part of most of the leftist reporting I've seen. The only instance I've heard of where a specific Twitter account has been accused of being a Russian misrepresenting their nationality was ian56789, and that accusation was false, as he demonstrated by going on Sky News and giving an interview.
What counts as "misrepresenting their nationality"? I'm sure russian bots aren't going around saying "I, John Smith, an American citizen, think that Hiliary is bad". It's probably going to be some user named @johnsmith2009 saying "Hilary is bad".
If your name is Misha Ivanovich, you're working out of Moscow, and you've got an American flag avatar, post mostly about US politics, and go by the name @johnsmith2009 on Twitter, I'd say it's clear you're doing some deliberate misrepresentation.
While I don't claim to have researched this issue in depth and it's worth taking this with a pinch of salt, I'm yet to see any evidence of this, nor has it been a part of most of the leftist reporting I've seen. The only instance I've heard of where a specific Twitter account has been accused of being a Russian misrepresenting their nationality was ian56789, and that accusation was false, as he demonstrated by going on Sky News and giving an interview.