Send email directly from a specific domain's control panel with relay server configuration enabled.

I need to send emails from an application hosted on one of my control panels using the panel's own hostname, IP address, and reverse DNS to a specific subdomain.

I have other domains on the same panel that send emails via a relay server defined in the web interface.

Is it possible to create a rule through the interface that, when the domain in question needs to send an email, sends it directly from the panel without going through the relay server?