There previously was a support page with the answer, but since Huawei removed it, here I go
(I think it was https://consumer.huawei.com/en/support/content/en-us00692700/)
I had a issue with my ArchLinux KDE computer where sometimes (when I used cpupower-gui I think), my computer would enter a "mode" where charging the computer would reduce the frequency of every core to 400MHz
The issue would then appear everywhere, even in the UEFI (and yes, the lag was noticable, even there)
From what I remember, here are the instruction that were on the Huawei support page :
(computer on)
- plug the charging cable
- Shutdown the computer by force, by holding the power button for 10+ seconds (continue even when it's off !)