Multilingual Digital Marketplace – How to ?

Hello,

im working on a Digital Marketplace (theme: Marketify) and i want to have it in different languages. But thats not all, because that would be not a problem.

The problem: The downloads which are added by members on the german translated site should be only visible for the German/Austrian user. So if a American user visit my website in english, then there should be not the downloads which was added by germans/austrians.

If a American(english speaking user/member) want to search german downloads (sorry, i dont want say what exactly ?? ) then he need to switch the language to german.

Same for other languages like spanish, french, swedish etc.

Do i need to have for every language a seperate webserver & domain or does it work thru a plugin ?

It wouldnt be a problem if that plugin will be not for free, my priority is that it will work like i explained :).

I`m sorry for the bad explanation and my bad english.

Thanks in advance!