Show variation SKU under title

add_action( 'woocommerce_single_product_summary', 'mx_show_sku_variable', 5 );
function mx_show_sku_variable(){
   global $product;
   if ( ! $product->is_type( 'variable' ) ) return;
   echo '<div class="sku_info"></div>';
   wc_enqueue_js( "
      $(document).on('found_variation', 'form.cart', function( event, variation ) {
         $('.sku_info').html(variation.sku);
      });
   " );
}