The device must typically be put into Qualcomm HS-USB QDLoader 9008 mode. This is often achieved using physical test points on the motherboard.
Some older firmware versions have a bug where entering Safe Mode via the recovery menu allows a "Reset All Settings" command to clear the FRP lock without a PC. shariff100-huawei-edition-reset-frp-qualcomm
The phone is powered off and connected via USB while shorting the test points to enter EDL mode. The device must typically be put into Qualcomm