China is probably not yet ready to mount a complex air-sea invasion of Taiwan, with the mighty USA at its back. But it would have no real difficulties making land invasion into Russia.
Taiwan… not yet, too hard, but Russia is officially a GO opines our dunk tank subject, further free military advice for China can be found in the article
“Attack your biggest ally so we can have easier time attacking you later. Sincerely, your biggest enemy” - nothing more than that, and even US diplomats are like that just not this openly, so what you expect of some random journo.