Apple Intelligence is not available on iPhones produced for China market

Switching region won't help

If you’re planning to use Apple Intelligence features and purchased iPhone in China mainland, you’re out of luck. Apple Intelligence is explicitly disabled for these devices even if you set supported system language and region.

You should check iPhone model number to understand, if model is produced for China market. Model numbers ending in “CH/A“ should be avoided if you’re planning to use Apple Intelligence.

Reference: PSA: You can’t use Apple Intelligence on devices purchased in China