@mnlsr, if you want the order by addition in the favorites list, this will work:
<ul>
<?php
global $wpdb;
// in author's page, I show the last 3 favorites
$favorites = array_reverse(get_user_favorites($author));
$results = $wpdb->get_results('SELECT p.ID, p.post_title, p.post_name, FIELD(p.ID, ' . implode(',', $favorites) . ') ord
FROM ' . $wpdb->posts . ' p WHERE p.ID IN (' . implode(',', $favorites) . ') ORDER BY ord LIMIT 3');
foreach($results as $res) {
echo '<li><a href="' . get_permalink($res->ID) . '">' . esc_html($res->post_title) . '</a></li>';
}
?>
</ul>