Introduction
The purpose of this article is to provide guidance on how to add subdomains and addon domains owned by another domain's cPanel account to a different cPanel account.
Procedure
1. Log into WHM and go to Tweak Settings.
2. Search for "Allow cPanel users to create subdomains across accounts" and set the value to "On".
3. Click Save at the bottom of the page.
More information on this tweak setting can be found here:
https://docs.cpanel.net/whm/server-configuration/tweak-settings/#domains