Microsoft documents replacing the ACPI table with their API: https://learn.microsoft.com/en-us/windows-hardware/drivers/b... (bottom of the page)

Unfortunately you need to disable signing for that, which will trigger anticheat in online games and makes Windows nag you about it.

Someone wrote a bootloader specifically to patch ACPI on boot in CSM mode if you're okay with reinstalling Windows on an older system that can't play certain games: https://github.com/MovAX0xDEAD/ACPI-Patcher

IIRC you can resign everything with your own key, but anticheat might still explode about it.