I haven't mentioned anyone there myself, but you can find posts with @mentions with Chinese characters (e.g. <https://weibo.com/1455818357/Q1uFeoKLf>;).
Also, the username seems to be unique as you can link to the profile by it (<[https://weibo.com/n/w3c中国](https://weibo.com/n/w3c%E4%B8%AD%E5%9B%BD )>)
