Android 9.0 for the X92 is almost always custom firmware (ROMs) developed by the community or specific vendors. Common sources include:
Once, it was the future. A promise streamed through HDMI: Android 9.0 Pie. 4K. 64-bit. Octa-core. You bought it from a listing with broken English, shipped in a plain brown box, no brand except the one printed in a generic font. x92 firmware android 9
The X92's LED turned from blue to blood red. Android 9