Is it possible to change the main website on a subscription in Plesk?
Such functionality is not implemented in Plesk at the moment. Vote for adding this feature on our UserVoice.
Each subscription in the Plesk is referred to by the domain name of the first website created under that subscription. The first website is used as the main domain of the subscription. Its virtual host directory is used for the document root of additional domains in the webspace.
It is not possible to set up an additional website as the main website on the subscription. The main website on the subscription cannot be deleted or replaced with another domain.
As a workaround, it is possible to rename the main domain of a subscription
Plesk 12.x and above
Go to Home > Subscriptions > example.com > Websites & Domains > example.com
Note: in case of Web Admin license is used, select the required webspace(subscription) in the upper right corner and click on Hosting Settings for the required domain.
Note: the permission "Domain creation" should be enabled on the subscription. The customer cannot rename this domain without this permission.