new-reply-to.php

<?php

// replace reply-to email address for WooCommerce customer emails

add_filter( 'woocommerce_email_headers', 'new_customer_order_reply_to_email_address', 20, 3 );
function new_customer_order_reply_to_email_address( $header, $email_id ) {

	$customer_email_ids = array(
		'customer_on_hold_order', 
		'customer_processing_order', 
		'customer_completed_order', 
		'customer_invoice', 
		'customer_new_account', 
		'customer_note', 
		'customer_refunded_order', 
		'customer_reset_password',
	);

	if ( in_array( $email_id, $customer_email_ids ) ) {

		$header .= 'Reply-to: <[email protected]>\r\n';
	}
	return $header;
}