Show Best Seller Products in Empty Woo Categories

woo-show-best-seller-products-empty-categories.php

<?php
// https://woocommerce.github.io/code-reference/files/woocommerce-templates-archive-product.html
add_action('woocommerce_no_products_found', function () {
    // Display the bestsellers    
    echo '<h2>Our Bestsellers</h2>';
    echo do_shortcode('[best_selling_products per_page="6" columns="3"]'); // https://woocommerce.com/document/woocommerce-shortcodes/products/

    // Display a button to go to the shop page    
    echo '<div class="ct-container">';
    echo '<a class="ct-button" href="' . esc_url(get_permalink(wc_get_page_id('shop'))) . '">All Products</a>';
    echo '</div>';
});