I have Xiaomi 3T Buds Pro Global version, and the advance options for the buds are not showing in the Settings on xiaomi.eu MIUI 14.0.1.0.
Since the xiaomi.eu rom are based on MIUI CN, your 3T Buds CN version might have the additional options in the Settings as the buds and MIUI are both CN. If not, then you can download the Xiaomi Earbuds app in the PlayStore.
If you have free time, please update here if you see all the features in the native Settings menu.
Thanks!