Sonarqube already has an email notification feature.
The documentation Notifications | SonarQube Docs doesn’t mention how to subscribe to notifications though - at least i didn’t find it.
Overall notification for all projects you have permissions,
as admin i use this as a kind of heartbeat monitoring, getting mails for everything
or notification per project
The user assignment to issues works like mentioned here Issues | SonarQube Docs
Login and email correlations are made automatically. For example, if the user commits with their email address and that email address is part of their SonarQube profile, then new issues raised on lines where the user was the last committer will be automatically assigned to the user.
Additional correlations can be made manually in the user’s profile (see “SCM accounts” in Authorization for more).
Even better is it to use the Sonarlint IDE plugin, to get issues BEFORE commit.
Note that Sonarlint doesn’t support all language scanners.