Reuters reports that Apple Intelligence in China will run on a large language model Apple trained itself, in partnership with Alibaba. Qwen features in the Chinese version too, with the Apple-trained model doing the primary work.
In the US and most other territories, Apple Intelligence uses Google Gemini technology, while its Foundation Models are entirely Apple's. Apple has also shipped ChatGPT extensions for Siri, and none of those options, Gemini, ChatGPT, or Anthropic's Claude, are available in China.