Current State:

Each notification send out from Jira will go through checks if the Account have been verified and has access the site. In some cases, for example, Jira Service management customers, they didn't log in to the site, as it only communicates via email. But the email account domain is part of users' approved domain , which means the admin is already aware of this account creation on the site.

Unfortunately , for the account to receive notification from this site , the account must be verified and login to the site , atleast once.
 

Proposed Future State:

Allow approved domain account to receive notification without the need to verify account and login to the site.
 

Alternative (e.g. Third Party Plugin):

No workaround