One solution that I use and like because it is reliable, is to change the BIOS to "Power On" after a power failure and use a smart plug to turn on the computer.

So turning the smart plug on my phone on would start the computer. I use it for my backup server with a JBOD that is only turned on when I need it. You can also schedule on/off time on the app. And if you want to programmatically turn it on/off you can setup Home Assistant with the plug.