See this video, it helped me:
netsh interface portproxy add v4tov4 listenport=<port-to-listen> listenaddress=0.0.0.0 connectport=<port-to-forward> connectaddress=<forward-to-this-IP-address>
for example
netsh interface portproxy add v4tov4 listenport=3000 listenaddress=0.0.0.0 connectport=3000 connectaddress=172.30.16.3
Microsoft has published a little bit of information about this on their WSL1 to WSL2 comparison page