Hi,
In multisite, the plugin has to make separate search queries for each database table – where the order of the results is separate for each site.
It might be however possible to re-order them via a custom code to date descending. Try adding this custom code to the functions.php in your theme/child theme directory. Before editing, please make sure to have a full site back-up just in case!
add_filter( 'asp_results', 'asp_reorder_in_mu', 10, 1 );
function asp_reorder_in_mu( $results ) {
usort($results, 'asp_date_compare');
return $results;
}
function asp_date_compare($a, $b) {
return strtotime($b->date) - strtotime($a->date);
}