There’s been some speculation about this on the forum but haven’t seen anything definitive about how ethernet can be setup on Gweike Cloud without the panel.
Here’s a video from Gweike about Wifi. It’s possible that the ethernet device is configured to the same IP or possibly another IP on the same subnet. From the video it looks like Wifi address defaults to 192.168.20.1.
Tutorial of Gweike Cloud WIFI Connection - YouTube
Here’s a link to a topic that discussed ethernet setup for the OmTech Polar laser which is a closely related device.
It’s likely that Gweike is setup similarly. The Polar has a default IP of 192.168.1.100. It’s likely that Gweike does something similar and defaults to a specific IP. I would look at perhaps these addresses:
192.168.1.100
192.168.20.1
192.168.20.100
If you’re familiar with networking perhaps you could scan across a wider range of addresses to identify the IP.