Neooostef

I have found a solution.
 
I have compile a specific overlay for disable Ethernet "gmac1"
 
nano radxa-zero3-disabled-ethernet.dts
/dts-v1/; /plugin/; / { metadata { title = "Disabled Zero 3W Ethernet"; compatible = "radxa,zero3"; category = "misc"; description = "Disabled Zero 3W Ethernet."; }; }; &mdio1 { status = "disabled"; }; &gmac1 { status = "disabled"; };  
and after 
 sudo armbian-add-overlay radxa-zero3-disabled-ethernet.dts
 
after reboot, all work fine
neooo@radxa-zero3:~$ sudo tcpdump tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on wlan0, link-type EN10MB (Ethernet), snapshot length 262144 bytes 13:05:31.533450 IP radxa-zero3.ssh > 192.168.1.118.50080: Flags [P.], seq 776960108:776960316, ack 799701818, win 501, length 208 13:05:31.581864 IP 192.168.1.118.50080 > radxa-zero3.ssh: Flags [.], ack 208, win 1024, length 0 ^C 2 packets captured 9 packets received by filter 0 packets dropped by kernel  
Thanks for help