How to display pending posts on the homepage only for editors

I would filter pre_get_posts.

function allow_pending_posts_wpse_103938($qry) {
  if (!is_admin() && current_user_can('edit_posts')) {
    $qry->set('post_status', array('publish','pending'));
  }
}
add_action('pre_get_posts','allow_pending_posts_wpse_103938');

That should show pending posts to your editors for all of your queries on the front end. You can, of course, restrict is more if you’d like.

I’d add some code to mark the pending posts so your editors know at a glance what is pending.