Get IP address of Windows 10 host through WSL2. MobaXterm's X11 forwarding seems to work only when you set the DISPLAY variable to the LAN IP address of the Windows host itself and not the VM IP or 127.0.0.1.

get_windows_ip.sh

#!/usr/bin/env bash

# example output
# regex in mywinip can be replaced with the following to snag more private subnets:
# '^.*(192\.168|10\.|172\.1[6789]\.|172\.2[0-9]\.|172\.3[01]\.).*'
# but it *will* catch the 172 address assigned to the VM/as gateway as well
# 
# mygw: 172.20.192.1
# mywinhost: DESKTOP-N2VKDIR
# mywinip: 192.168.0.39

mygw=$(cat /etc/resolv.conf  | grep -v '^#' | grep nameserver | awk '{print $2}')
mywinhost=$(host ${mygw} | grep -Po '^.*pointer \K(.*)' | tr -d '.')
mywinip=$(host ${mywinhost} | awk '{print $4}' | grep -E '^.*(192\.168\.0).*')

printf "mygw: %s\nmywinhost: %s\nmywinip: %s\n" "${mygw}" "${mywinhost}" "${mywinip}"