ADD SAMPLE TO MULTIPLE PRODUCTS workaround

Here is a little loop to add the sample option to multiple products
This will set the sample price to 0.50
Please note, if you set a category with a lot of products this may break the internet

<?php
    $args = array( 'product_cat' => 'your-cateogry-name-here', 'post_type' =>  'product','posts_per_page' => '-1' ); 
    $postslist = get_posts( $args );    
    foreach ($postslist as $post) :  setup_postdata($post); 
    ?>  
    
   <?php  add_post_meta( $post->ID, 'sample_enamble', "1" ); ?>
   <?php  add_post_meta( $post->ID, 'sample_price_mode', "default" ); ?>
   <?php  add_post_meta( $post->ID, 'sample_price', "0.5" ); ?>
   <?php  add_post_meta( $post->ID, 'sample_shipping_mode', "default" ); ?>

    <?php endforeach; ?>