I doubt anything of that sort will happen! China has already come down heavily on bitcoin and I am sure Chinese elites will not take such risk unless and until they want to flee out from the country. Even if some elites decide to use cryptos to safeguard their wealth (which is highly unlikely) they will use a portfolio of cryptos.

It's true that the trade was escalated pretty quickly, but don't think China depends only on US. They have retained number one position in international exporter's list since 2009. The trade war will definitely impact them, but not to that extent where they will have to find an alternate way!!