// force URL rewrite for QRh
function custom_rewrite_rule() {
    // Adding a rewrite rule that maps the new URL to the internal query for product-category/outlet.
    add_rewrite_rule('^tienda/outlet/?$', 'index.php?product_cat=outlet', 'top');
}
add_action('init', 'custom_rewrite_rule');

function custom_rewrite_tag() {
    // Adding the custom query var to ensure WordPress recognizes it.
    add_rewrite_tag('%product_cat%', '([^&]+)');
}
add_action('init', 'custom_rewrite_tag');