I don’t think your LAN eth0 ist working properly, why it has so much “Retr”, and WLAN has 0 “Retr”?
I have also X96_x4 1000M Rev 1.3, it has other PHY.
And did iperf3 benchmark with coreelec-ne, Kernel 5.4.125, and got better results:
What Board Rev. is it?