add_action('wishlist_archive', 'wishlist_archive_20201908', 5);
function wishlist_archive_20201908($atts){
//echo '<pre>'.var_export($atts, true).'</pre>';
?>
<span>Custom HTML here</span>
<?php
} 
add_action('wishlist_archive', 'wishlist_archive_20201908', 5);
function wishlist_archive_20201908($atts){
//echo '<pre>'.var_export($atts, true).'</pre>';
?>
<span>Custom HTML here</span>
<?php
}