Running on orangepi as USB router?

Can OpenWRT configure USB port as networking dongle? Not sure if my terminology is right, so here's a long explanation of the idea.
I have a home server and would like it to do routing as well, as I already have too many boxes around. I understand that running router as VM is a bad idea, so I see another option - installing a small orangepi or similar SBC inside my server's enclosure, and running OpenWRT on that. The idea is to connect my WAN to SBC, then routing happens and traffic is carried via USB to my server, where it sees it as USB ethernet card, bridged with server's ethernet port, which then connects to my switch. Basically:
WAN_modem_[RJ45] -> [RJ45]SBC[USB] -> [USB]server[RJ45] -> switch/LAN
For this to work, I think I can connect it via internal USB, but then OpenWRT should configure SBC's USB port so as my server would see it as USB ethernet card. Is this possible?

Edit: in other words, what I want to do, is run OpenWRT on a USB NIC dongle. Like this

Yes, you can use an USB NIC.
You can't run openwrt "on" it,, but you can use it for your networking.

I want to use it AS USB NIC. I believe it's called reverse tethering?

it is an USB NIC ? :slight_smile:

AFAIK tethering is a term for connecting cellphones via an USB cable, or wirelessly.

[OpenWrt Wiki] Smartphone USB tethering

I believe I have found what I was looking for. It's called "USB gadget mode".
Further research required, as it seems some SBC chipsets only support host mode.