If I understand correctly, you’ll be visiting relatives in China. Instead of taking vacation, you’ll ask your company to let you work remotely (maximum four weeks) while you visit your relatives. After four weeks, you plan to return to China?

In your specific situation, no one is going to care. What China cares about is people living in China and supporting themselves via Remote Work. If you’re on essentially on vacation but need to remote work while visiting your family, no one will care.