I see option ifname eth0 in one place and eth0.1 on another network. That is wrong. It appears that eth0 isn't hardware connected to anything-- but if it were you would decide whether or not to use VLANs on the ethernet port. Then use either eth0.X (X a different number for each VLAN) for all your interfaces, or if not using VLANs, plain eth0 on one network. Don't do both.
"It's their firmware" is because it is a manufacturer build, not something that can be obtained from downloads.openwrt.org. It appears to be close to an official build but not exactly.
Those words and buttons don't exist in OpenWrt. I'd definately be worried about those buttons on the wireless page, since we don't know what they do.
Now, ask the OEM why it's there - it may be a syntax difference preventing you from enabling the WiFI.
SMH...you have to ask the OEM to tell you and/or provide a diagram of the network design. In normal OpenWrt, its connect to a switch that has to be enumerated by VLANs to the ports (e.g. eth0.1 bridged to WiFi for LAN and eth0.2 for WAN).
What is the overall system like? This is a module that plugs into something larger. Is there any actual Ethernet hardware involved that would be connected to eth0 on the CPU? It looks like everything goes over USB with an Ethernet-like "gadget" driver.
A little bit I found later and It was a little joke. Sorry if it was not funny for you
It works as a power supply and it is an Ethernet over USB.
Ok. I supose that you can not help much more with that. There are too much aspects which are not clear. Thank you so much for your interest @mk24@lleachii and @anon50098793. I will close this topic and I might resume in the future if I have got more information.
I found later and It was a little joke. Sorry if it was not funny for you 