As far as I could tell Virtualizor does not have direct support for Clientexec but has support for WHMCS & Blesta.
I did find this concerning my question, however, I'm unsure if the GitHub linked is up-to-date with Virtualizor: clientexec.com/addons/clientexec/server/virtualizor
If you could confirm that it is, I'd appreciate it!
Hope to receive a response from you soon, thank you!
Solved in ticket, please close