Modify entry comments in WordPress according to the e-mail address.

functions.php

// Modify entry comments
function qr_admin_author($comment_data){
    if ($comment_data['comment_author_email'] == 'mail@domain.com') {
      $comment_data['user_ID'] = 1;
      $comment_data['comment_author'] = 'Author Name';
      $comment_data['comment_author_url'] = 'Author URL';
    }
    return $comment_data;
  }
add_filter('preprocess_comment','qr_admin_author');