Not sure about stock index futures, but in general foreigners can trade the "A-shares" of Chinese companies at the STAR exchange (similar to NASDAQ), and also of other domestic Chinese exchanges: https://www.ubs.com/global/en/asset...ect-china-a-shares-faqs-equity-investing.html
"China A-shares are RMB-denominated equity shares of China-based companies that trade on the Shanghai and Shenzhen Stock Exchanges."