SDANG!
Update the falang component solved the alternate link issue.
About the original topic: checking on google search console the live URL (not the ones that have been already crawled) seems that .../product/lising pages now show the correct canonical url. So I'm quite optimistic we have solved, at least, part of the excluded pages. Need to investigate more in the next days.
On local I'm testing the Custom Canonical Plugin (
extensions.joomla.org/extension/custom-canonical/
)
Do you know it? Limiting its use to just articles and joomla categories, without touching the default canonical, seems to work well with Hika,
So, for the moment I'm ok, I'll be back here if new question about SEO will arise in the next days.
Thank you very much Nicolas, your tips are always very useful!
Have a nice day.
Davide