"Russia" is a big place. The Mongols set up a mafia holding state with the Muscovites around 1230, so never actu@lly lived and reigned there. They did disrupt the areas further south towards the Caspian and tried but failed to gain a foothold in Crimea a hundred years later. It was that period when they *brought* the bubonic plague to the west (whether from Wuhan, dunno), and actively launched diseased bodies into the besieged city of Caffa, from which the refugees spread it to Europe. You can imagine that neither case is a great marketing pitch for "accept lots of Orientals to your territory", even though remnant Tatar and Bashkir autonomous regions still exist southeast towards the Urals, thanks to Lenin mostly.

But yes, it's possible with China's building military might that they could invade Russian territory to annex fields of wheat, though realize thatthe Chinese population will fall by 1/2 by 2100, so what's pressing now won't be pressing then. (Russia's population and might will almost certainly contract by then too).