Hi,
That is because I activated the generate canonical url automaticaly?
Yes, that, and also because you have canonical URLs in the product but not in the translations of your products.
With sh404sef, I guess it would be possible to keep the language through clicks?
sh404sef or not, it's not related to the problem.
I would have to deactivate the generate canonical, remove any canonical of products and categories?
No. Just turn off the "force canonical URLs on listings" setting or enter canonical URLs in the translations of the products.
You don't have the remove the canonical URL of the products. Of course, that would also be a solution.