Connect RAK7246G through LAN to router

Issue: I wanted to connect my RAK7246G gateway with an adapter (LAN to micro-USB, image below) via LAN to my router. When accessing the “Configure LAN” option in the gateway setup it just says: your device doesn’t support LAN configuration. Now I’m wondering if I can connect my gateway via LAN nonetheless but with some manual work. And if that’s indeed possible how I would accomplish it.

Setup: RAK7246G

Details: I am using a RAK7246G, but couldn’t choose that in the category selection. Image: The gateway with the adapter I wanted to use:

The RAK7246G gateway is based on a Raspberry Pi ZERO and has no Ethernet port.
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The only way to connect it is over WiFi.