https://www.resellerclub-mods.com/whmcs/business-enterprise-email-module.php

The Resellerclub Panel allows its resellers to resell, Shared Hosting Services, allows Linux Hosting Resellers, Windows Hosting Resellers, VPS Servers, Dedicated Servers, SSL Certificates and others.

The professional email services module is very important, it can be developed by an expert and sell it if you want it is important. in WHMCS these modules exist.

Here it is not possible to resell professional email services, combo plans, everything is limited here. the module can be sold but it is important that these resources arrive, that would increase the power, I had friends 15 people to use WISECP due to the lack of these resources, they retreated to buy licenses here.