Hi,
Depending "where" the email has been sent, the address_template can be load from the "front-end" part or from the "backend" one.
Please put your address_template override for both parts.
We will made some tests for the language override in the email but in order to make it in the same context than your, would it be possible to know how the order notification is send ?
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.