Adding template related actions

What does the code you currently have look like?

You would have to check there in the function in which context it is called. If you only execute the new product template for certain products, you could check this in the following way:

add_action( 'woocommerce_single_product_summary', 'promo_alert', 20 );
function promo_alert() {
    $post = get_queried_object();
    $product = wc_get_product($post->ID);
    if( in_array($product->get_id(), [42]) ) {
        return;
    }
    echo '<strong>WORLDWIDE SHIPPING rates...  ...notifications.</i><hr>';
}

In the example, the product with ID 42 is excluded from displaying the hint.

Unfortunately I don’t know how you assign the template to the products. If necessary, you can also use this as a criterion by accessing the product object.