I’ll answer my own question just for the sake of history, in case somebody will be looking for an answer )
So I got Intel Arc B580 (Intel Limited Edition card), Minisforum DEG1 OcuLink dock and OcuLink m.2 adapter from kyle_tuck. Connectedd all together and… Nothing. Dead silence. Dock sees the laptop, it turns on and off when laptop is being turned on and off accordingly, Fans on the B580 spin, but other than that - neither Windows 11 nor Linux don’t see the card at all. lspci, dmesg - not even a characther related to the card.
Digging the internet a little bit I came across similar issues here and there. And the official answer from Intel is that ARC GPUs do not officially support OcuLink. If it works - it’s a luck. Seems in my case it’s not (
Unfortunately I don’t have any other GPU to test that dock works at all, and I need to test the GPU itself with the desktop system to eliminate that uncertainty as well… Will keep posting here my observations in case something changes
I like how it looks tho 
