The president-elect wrote that the coalition of non-Western countries “should expect to say goodbye to selling into the wonderful U.S. Economy” if it backs a currency other than the U.S. dollar.
No "like", he is. Russia and China want to devalue the dollar and replace it as the world currency.
Obviously Russia is unlikely to achieve that, but I'm sure China encourages the use of RMB in their global operations, like in their belt and road projects.
Russia benefits from a stronger US dollar insofar as its oil and gas exports are settled in that currency. The more valuable the US dollar is (as measured against the ruble), the more rubles Russia's exports end up yielding — or the better they compete with other producers in international markets.