So just to be clear, you think that Trump and the GOP are so bad you would welcome Xi or Putin launching an assault on US soil and depose him?
To push your point even further: do you feel so strongly that you would volunteer to help?
This already happened. Trump lead a Russia-backed coup against the United States in January, 2021 to overturn the 2020 election and illegally take the presidency. It failed, but he and every government employee who supported him after that is guilty of treason and is serving illegitimately.
Trump is president because he was elected by the American voter while the opposition was in power. I would not label that as illegitimate and I think it is dangerous to spread that narrative.
https://en.wikipedia.org/wiki/Fourteenth_Amendment_to_the_Un...
Was he tried and convicted? If his successor and the opposition truly believed that why did they not go after him for it?