[Crssi]

You can fake PowerOn/PowerOff... and it works.
PowerOn is allways the same, since BIOS is expecting that for powering on sequence.
But PowerOff is controlled by operating system.
So, you can set some other sequence in the operating system to be PowerOff.

When NUC is powered off it will pick PowerOn sequence to turn.
When NUC is operating, then operating system will simply ignore PowerOn sequence and will respond only to your designated power off sequence to sleep/TurnOff (whathever you choose to be in OS).

Then you set/fix on harmony power method and leave PowerOn as is and set the other sequence you have choosen to be PowerOff.

Voila... it works for me 100%.