Code-Snippets-Functions/Execute a function on a child site/WooCommerce/add-cc-or-bc-to-customer-email.txt

add_filter( 'woocommerce_email_headers', 'wc_order_completed_email_add_cc_bcc', 9999, 3 );
 
function wc_order_completed_email_add_cc_bcc( $headers, $email_id, $order ) {
    if ( 'customer_completed_order' == $email_id ) {
        $headers .= "Cc: Name <your@email.com>" . "\r\n"; // del if not needed
        $headers .= "Bcc: Name <your@email.com>" . "\r\n"; // del if not needed
    }
    return $headers;
}