customize email order status by products ORDER_STATUS_NOTIFICATION_SUBJECT

-- HikaShop version -- : 4.4.0
-- Joomla version -- : Joomla! 3.9.18
-- PHP version -- : 7.3

Hi,
for a very specific product i have, i would like to modify the email subject sent on order notification.
I have customized the email template to do this and it works fine, but cannot see the option to override the email subject by a similar condition.
perhaps i can add a parameter to the language string ?
ORDER_STATUS_NOTIFICATION_SUBJECT
Would like your help and guidance
Thanks

Thanks