Thank you Nicholas for this new feature.
I have 2.1.2 installed and was hoping to resolve this issue with my client, but I think I may have found a bug.
The canonical url for the translation (using the tab in the product page) will not let me save anything other than the canonical url of the product in its original language.
For instance:
Target url in french:
www.productionstanicet.com/duet
Target english version:
www.productionstanicet.com/en/duet
In the product *duet*, I add: */duet* for can. url
In the trans tab, I add: */en/duet*
When I save, the trans tab reverts to */duet* (which is what is rendered in the page source too)
I do have a workaround, I can go through the Falang component, locate my products and update the canonical urls there (which are saved properly). However, I must publish them to complete the process. I thought Hikashop directly used the Falang tables...but after considering my workaround, I am a little confused.
Anyhow, just a heads up - and thanks again for the feature!