I suggest to add in the footer the direct link to unwatch the page.
See https://de.wikipedia.org/wiki/MediaWiki:Enotif_body where this is implemented.

See https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/core.git;a=blob_plain;f=includes/UserMailer.php;hb=master lines 643 seq. if you want to learn which parameters can be used and how they are computed.

Dear $WATCHINGUSERNAME,

The {{SITENAME}} page "$PAGETITLE" has been $CHANGEDORCREATED on $PAGEEDITDATE by $PAGEEDITOR, with the edit summary: $PAGESUMMARY $PAGEMINOREDIT

$NEWPAGE See $PAGETITLE_URL for the current revision.

To contact the editor, visit $PAGEEDITOR_WIKI

Note that additional changes to the page "$PAGETITLE" will not result in any further notifications, until you have logged in and visited the page.

Your friendly {{SITENAME}} notification system

This email notification feature was enabled on English Wikipedia in May 2011 - see {{canonicalurl:Help:email notification}}.

If you would like to modify your notifications, visit
{{canonicalurl:{{#special:Preferences}}}}

If you wish to remove the page from your unwatch, visit
$UNWATCHURL

Feedback and further assistance:
{{canonicalurl:{{MediaWiki:Helppage}}}}

Version: unspecified
Severity: enhancement
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=28026