I have similar, but different issue with configuring GT-AX6000 as AiMesh node connected to GT-AX6000 primary router. I started another thread a couple of days ago:
GT-AX6000 as AiMesh Node?.
I have the issue as described in the the other thread whether the node is directly connected to primary router or connected via TP-Link TL-SG3210XHP-M2 1.0 10/2.5 Gbps managed switch. I have other AiMesh nodes (
(2) RT-AX86U (2.5 Gbps wired backhaul) and RT-AX82 (5 GHz 160 Mhz wireless backhaul)) that connect and operate as they should.