Justin Sun, founder of the Tron blockchain and the man who runs the Huobi crypto exchange, is ready for that change. He said in a tweet Monday that Huobi would apply for a virtual asset service provider (VASP) license in Hong Kong under new requirements to operate that go into effect in June. If approved, the exchange would then launch Huobi Hong Kong.

The Chinese government's relationship with crypto has been tumultuous. Two years ago, regulators cracked down on crypto trading and mining.

Sun thinks China is looking at Hong Kong as a kind of experiment, to see if crypto can be regulated on the mainland. If Hong Kong suceeds it could create a change of attitude in Beijing. "So that's why they want to see Hong Kong do it first," he said. "And then you see the result. If it has positive feedback, they might change the policy in mainland China as well."