cwcfp_send_field_details_to_customer filter lets you determine whether or not to add the conditional field details to the order emails that are sent to the customer.
The filter expects a boolean result (true or false). By default, it returns true, which enables the conditional field details to be included in the order emails.
/** * Prevent the conditional fields from being added to the customer email. */ add_filter( 'cwcfp_send_field_details_to_customer', __return_false );