Well given the Qing came from there, does this more limited realm remain broadly similar while the Ming dominate the rest of China (sans Mongolia and Dzungar)? If so, and the Ming’s successors mostly take over old lands, then it’s likely these territories all fall into Russia’s sphere of influence, if not outright annexation. With how Manchuria in otl only managed to become assimilated to China properly in the late 19th century, and that was after centuries of Qing excsptionalism, I imagine Russia could have assimilated an independent Manchuria similarly, as they did in outer Manchuria in otl. In fact without Qing protectors in Beijing, they’d probably do so much earlier ITTL. Outer Mongolia and Xinjiang are probably more difficult to integrate, and are likely an extension of OTL’s Great Game.