Some phones use USB-C standard but it’s just wired for data and charging (so basically micro USB in USB-C format), so I think depending on the adapter/phone it can’t work.
To back this assumption I just tested my Nokia 7.1 on an USB-C dock and only thing that works is the USB hub, no LAN.
If it helps, I have an old version of /e/OS on my XA2, and I tried to connect a USB to ethernet adapter (with a USB A to USB C adapter; I know that this one works on my XA2, since I have installed the /e/OS image with it).
The result was no internet connection (and there was internet connection with wifi, so it should not be an issue coming from the router). It might be either the phone /OS (although the connection of the accessory was recognized, since the phone asked me if is has to be used with the app downloads…), or the USB to ethernet adapter itself (I used the one a logo of fruit on it … It works with other devices).