1) Product SKU is the WooCommerce plugin option. Our theme does not have special settings to hide SKU if the parent SKU is not added. So, contact WooCommerce support about this https://wordpress.org/support/plugin/woocommerce/
2) Don’t understand your question about “More Sorting Options for WooCommerce” plugin. Could you, please, explain in more detail and provide link to your shop page and temporary WP Dashboard access?
