Most users seek custom ROMs to get Google apps. Since ROMs aren't viable, these software-based workarounds are more common:
While HarmonyOS isn't a "Custom ROM" in the traditional sense, it offers a much smoother experience than the stock Android 10 EMUI that many global MatePad 10.4s are stuck on. If you can find a safe guide to upgrade to the China HarmonyOS version (and live with the Chinese bloatware that you can disable), it is often a better experience than risking a bricked device with a GSI.
The Kirin chipsets used in these tablets have limited public documentation, making it harder for independent developers to build stable ROMs. 2. Potential Workarounds (Advanced Users Only)