Oh damn... sorry, i don't know why but i'm not getting the email notifications anymore (and i checked in my prefs...).
There isn't much need in me posting my EFI when you can simply get the one from this thread:
https://www.tonymacx86.com/threads/gigabyte-z490-vision-d-thunderbolt-3-i5-10400-amd-rx-580.298642/
The guide is very well explained and will get you going with absolutely everything, including native NVRAM and OSX CPU power management. I only made two changed:
1- created my own USB Map (i can post that if you want), but you should create yours because you might not want the same setup as me depending on the hardware you use, (for me, the internal USB2 uses the wifi and i have 2 USB3 ports to the front and most of my hardware is USB2, so with the 15 ports limit, i had to make choices and made sure USB2 stuff were working before USB3).
2- Added my own serial number, UUID, etc...
Regarding the GPU, i'm using a Sapphire RX580 nitro + and it's working like a charm, no drivers needed, i have two 4K screens attached (display port), and i could even add a third one to the DVI output (1980x1024). HDMI does not work though, but i don't really care that much, 3 screens is already enough