The Xiaomi Mi 9 smartphone has joined many other Xiaomi and Redmi devices on the Android 10-based Paranoid Android Quartz 4 custom ROM support list. The devs behind the firmware are also preparing the Xiaomi Mi A3 and Mi Mix 3 for future releases of the Paranoid Android ROM.
https://www.notebookcheck.net/Xiaomi-Mi-9-added-to-the-Paranoid-Android-Quartz-4-custom-ROM-list-with-support-for-the-Mi-A3-and-Mi-Mix-3-in-the-works.484003.0.html