PPPOE half bridge / passthrough

Hi, I would like to know if its possible to configure OpenWRT to handle the PPPOE session but passthrough all traffic to a backend device (Pfsense). So the backend device holds the public IP. So any traffic to and from the public IP goes straight through OpenWRT to the backend device.

I have a 1G FTTP connection. i have an ONT that just handles the fibre/copper conversion. Whatever connects to the ONT must establish a PPPOE session and that device gets the public IP.

Looking at this post - https://openwrt.org/docs/guide-user/network/wan/bridge-mode
The 'half bridge' section describes exactly what I am after "in this mode, the device handles authentication (the login/password of your Internet contract) and encapsulation, and it will duplicate the WAN IP address from the ISP to the downstream device"

I have tried to configure this but have not been successful.
And I have researched the topic in these forums but cant seem to find an example or an answer.

The reason i want to do this is because Pfsense has poor PPPOE performance but I like it as a firewall and I don't like the idea of double NAT.


PPPoA was able to reach half bridge solution but not PPPoE .
double NAT can be doable when 1to1 NAT is used .I've tested this for a while on VDSL and had 0 issues with upnpd or vpn . No outside IP but ports are mapped like if it was . Both devices ware OpenWrt but I assume DMZ would work same way on ISP hardware .

I guess Ill just use the standard firmware on the router then.
Don't really see what value OpenWRT brings, at least not in my case.