add_filter('woocommerce_related_products', 'wooler_change_related_to_cross_sell');
function wooler_change_related_to_cross_sell($products)
$cross_sells = array_filter(array_map('wc_get_product', WC()->cart->get_cross_sells()), 'wc_products_array_filter_visible');
$orderby = apply_filters('woocommerce_cross_sells_orderby', 'rand');
$order = apply_filters('woocommerce_cross_sells_order', 'desc');
$cross_sells = wc_products_array_orderby($cross_sells, $orderby, $order);
$limit = apply_filters('woocommerce_cross_sells_total', 0);
$cross_sells = $limit > 0 ? array_slice($cross_sells, 0, $limit) : $cross_sells;