How to change realted product thumbnail size in woocommerce single product page wordpress

For change the related product thumbnail size in single product page woocommerce paste below code in your theme's functions.php file

below code is tested and works fine.


add_action( 'after_setup_theme', 'rj_remove_loop_thumbnail_filter', 10 );
function rj_remove_loop_thumbnail_filter()
{
    remove_action( 'woocommerce_before_shop_loop_item_title', 'woocommerce_template_loop_product_thumbnail', 10 );
}
add_filter('woocommerce_related_products_args','rj_related_product_args');
function rj_related_product_args($query_args)
{
    if( is_singular( 'product' ) ) {
   if( ! empty( $query_args ) ) {
            set_query_var( 'related_products', true );
        }
    }
    return $query_args;
}
remove_action( 'woocommerce_before_shop_loop_item_title', 'woocommerce_template_loop_product_thumbnail', 10 );
add_action( 'woocommerce_before_shop_loop_item_title','rj_change_related_product_thumb',10);
function rj_change_related_product_thumb() {
    global $wpdb,$wp_query, $post;;
        $related = get_query_var('related_products');
      if( TRUE == $related ) {
          
                if ( has_post_thumbnail() ) {
                echo get_the_post_thumbnail( $post->ID, array( 200,200)  );
            } elseif ( wc_placeholder_img_src() ) {
                echo wc_placeholder_img( $size );
            }
        } else {
            echo woocommerce_get_product_thumbnail();  
        }
    }