Is there any workaround that we could use like routing the requests
from China to our own server and relay to GCP, or any other thoughts?
If your goal is to prevent legal issues in China, do not try to bypass their regulations, firewalls, etc. Technically, you would need to set up a VPN from a data center in China to your home office. You cannot use an endpoint in Google Cloud, AWS, etc. You will probably be restricted to only transfer traffic related to your business from your US office to your office in China. Do not forward traffic to businesses that are restricted by the government. That includes Google Cloud.
The best answer depends on who you are meaning are you an individual, small business, or a large company, and what type of business you conduct. Details such as merchant processing, etc make a difference.
China has laws regarding Internet access and a firewall to enforce them.
You have two options:
a) use a cloud service in China such as Alibaba. That is my recommendation. Do everything in China as a separate business that does not need Internet access outside China.
b) apply for a license from the government. That is fairly easy but takes time. There are multiple licensing tiers. If you process payments or financial transactions, the process is very difficult.
Consider retaining an agent in China to assist you with government regulations in China. Only a Chinese agent/business can apply for you. Unless you are a citizen, you cannot personally apply for yourself or your company.