We have Magento 2.1.1 installed, together with the "Porto" template and a second (german) language pack.
Language in the backend works fine.
Unfortunately, it works not with the language change in the store. On the home page, I can still change the language from english to german. Now my german main menu is visible. So far so good. If I select something from the german menu it jumps directly to a 404 - why? Because the language from the store jumps back to english and the URL .../german-category/germanarticle,html doens't exist for english.