@weirdobeardo48 

Hi,

The definition of "EasyMesh via Ethernet Backhaul" (i.e. wired backhaul) is that the Easymesh Satellite is connected by Ethernet cable to the EasyMesh Main router.
Connecting the Easymesh Satellite via cable to a router of a different subnet that is not part of the EasyMesh network can cause all sorts unpredictable behavior. 

Even a network of Deco devices is not intended to be setup like shown in your picture (with the connection (1)). 
Was your Main Deco device set to "Wi-Fi Router" mode or "Access Point" mode?

Hi  @weirdobeardo48,

If easymesh is established, the client devices under the easymesh network should all be in the same domain, that is, 192.168.80.x

There may be something wrong with your physical topology. The WAN port of the satellite router does not need to be connected to the LAN port of the ISP router. It obtains the network from the main router via wifi backhaul, so you can remove the Ethernet cable of the WAN port of the satellite router.

  @Joseph-TP 

yeah bro , as the main for easy mesh via cable which port connect from main to satellite ? In the case , devices are supported  easymesh with cable ? Lan from main to wan satellite or can we set lan to lan-satellite if wan's satellite  has error hardware