China should simply go into another jurisdiction and start investigating it's nationals? It doesn't work like that.

They already have an annual limit of $50,000 that can be transferred out of the country, they also ask foreign countries for help in identifying corrupt officials and individuals transferring large amounts out of the country, rich Chinese have strategies to avoid the law.

In my own country i've seen that request largely ignored. The benefits are simply too high, the Govt here is well aware that sizable portions of this money is likely dirty money, but the bottom line for the economy eases that discomfort.

The push to crack down on foreign housing investment in cities across the world lately has been driven by angry locals and soaring house prices, despite the Chinese govt asking for something to that effect for over a decade.