Firewall rules: send traffic from one IP address to another on same nework

[bonnietwin (Adolf Belka)]

@timattrn

The real problem I wanted to solve was to allow people on the one subnet (blue) to discover a IPP printer on green, and then have print traffic sent to it once it has been discovered.

That question seems to have already been asked by yourself in another post https://community.ipfire.org/t/printer-discover-traffic/10309 and appeared to have been solved with the use of the mDNS Repeater addon based on your last reply in that thread.