You can modify them on this files .../components/com_easysocial/themes/wireframe/emails/registration/moderator.approvals.php and applied customizes file at this path .../templates/*current_template/html/com_easysocial/emails/registration/moderator.approvals.php or you can modify them here http://take.ms/3Xrcf
Currently, we cannot configure them as those emails will be sent to all "Super Users" group's users and will check if and only if these settings enabled http://take.ms/UBtai, then they will sent out those emails(on Joomla User sections).