@Yakku AX55 doesn't support this feature. This is a list of routers supporting wireless connection to another modem/router.

@Gedikpasha Here's the title of the thread I mentioned: With the latest FW release for AX20 v3 Easymesh was added but not an ethernet backhaul:

@Gedikpasha No, but you already knew that - it's in your initial post. Here's the list of routers that support Easymesh over an ethernet backhaul. Two AX23 can build an ethernet backhaul.

@redsnowdonkey If you use the C80 in router mode you surely will introduce double NAT in your network. I would try both scenarios where C80 is in "manual" AP mode - details (Case 2) and check which...

@Flashnet1 Probably it would be best to contact your local support/retailer regarding any of the misbehaving devices. For that purpose you have to open and test all the devices, whether they would...

@sbatis This should be straight forward operation - check this story. Pay attention on the VLAN ID configured only on the router behind the bridged modem.