Multilingual Navigation issue

Hello community ! 

I've created an English SharePoint Site (default site language). I've activated the Multilingual option for French, Chinese, Arabic

Anytime i change my language preference in profile, and change the navigation, this applies to all users in all languages. 
I set prefered language to chinese, translate navigation in chinese ....  then change prefered language to english. Navigation menu still appears in Chinese. When i translate it in english, Chinese traduction is  gone for chinese people. 

Any clue ? 

Thanks