I applied all the patches in OC Configurator, regarded to USB and it works now. OpenCore Configurator -> Kernel -> Patch, then chose:
Disable Intel Fresco Logic USB 3.0 .... (both)
Disable Intel XHCI 1.0 check ... (both)
USB Port limit patch # 1/2 ...
USB Port limit patch # 2/2 ...
I dont know which of them made the trick, but it works for me.
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Intel i3, 8400, 3.60 GHz, 6M L3 cache; Gigabyte GA-Z370P D3, LGA 1151, Realtek ALC 887 audio codec, 1 x Realtek GbE LAN chip (10/100/1000 Mbit), XFX Radeon RX 580, 8G VRAM, Apple wired aluminum keyboard and Apple mouse; macOS 11.X Big Sur.