The WordPress manager provided by cPanel will allow you to be able to list the WordPress sites that exist on your cPanel account. Features that the WordPress manager in cPanel offers is to manage the existing sites on your cPanel account. The basic setting options which display within the WordPress Manager will be the site URL, how much disk usage is being used for that site, and the version of WordPress core that is installed on that site.
The WordPress manager does allow automatic updates of WordPress core to be updated. You can enable minor and security versions updates or you can enable all WordPress core updates. All WordPress core updates would include all minor and security updates as well as major updates. A major WordPress core release may include breaking changes will also mean that the active theme and active plugins will also need to be updated. The other options in the WordPress Manager include being able to update the main admin users password and being able to create or restore a backup of the site.
MainWP is different from the cPanel WordPress Manager in that it deals with WordPress core updates, being able to create a staging site for your connected child site, plugins and themes updates, and child site backups. MainWP also includes extensions for uptime monitoring, code snippets, bulk settings, and more. MainWP is self-hosted and open-source as well as offering so much more in the way of features and site management abilities that the very basic cPanel WordPress Manager does not offer.
MainWP is one of the most solid and feature-complete options out there to be able to manage your clients’ sites with.