回复：Help needed! 我现在是H1B Postdoc，有公司想以Part-time雇佣

If the future employer has registered division/branches in China, they can hire you from there and pay from there.
The porblem is some edutionational and research institutions do not allow you to take a second job. You can be violating immigration laws and breaking employment contracts.

Also, how do you plan on getting visas to come back to US? I do not think you can have a reasonable explanations at the US embassy.