Existing foreign products have applied for utility model patents in China. Is it effective?

According to the patent law, your application is not a big problem, but foreign companies can sue you for infringement. The reason is simple: people can produce original evidence and you don't, so even if you have a patent, your product may still be sued in the WTO. There is a 100% chance that you will lose the case, and your profit is not enough to compensate.