Hello,
Thank you for the clarification even if I'm missing an important point to fully understand the situation:
So when you're talking about "hika's default template" ; you need to be more precise.. HikaSHOP or HikaMARKET ?
I still don't know what is your final result ; what template is being used for hikamarket emails...
So, I will take a hypothesis that it's HikaMarket default email template (the green one).
Nevertheless, I've send a message to Nicolas in order to clarify how template should work with other components.
HikaMarket has the emails stored in the "media/com_hikamarket/mail/" folder and it provides also few templates.
Best is that you copy your template from "media/com_hikashop/mail/template/" into the HikaMarket one (and provide another name so it will be display correctly in the list).
By doing that, I think the customization should work.
In the meantime, I'll see how HikaShop and HikaMarket could share templates for their mails.
Regards,