Sometimes, we need to listen on the public server and redirect the traffic into our empire listener on the internal server using DNAT, we would like to set the listeners "Host" to the public IP address while listening on the internal server. This way, all the stager payloads would contain the public IP address while the EmPyre instance turns on the local machine. This pull request would allow us to implement this scenario.
On the empire powershell project, the listener listens by default to the 0.0.0.0 IP address (https://github.com/PowerShellEmpire/Empire/blob/e43fb9463410dfa804e0aa507a5842c1a0504c0d/lib/common/http.py#L150).