Here is a list of languages currently available on OGS. The language features can be accessed in your settings.
We’re trying to add more languages all the time. If you’re interested in helping us translate, drop us a line!
(I personally prefer the original EN, though, since my sense for both EN and DE is easily hurt … most often by German native speakers … when they use EN or DE 
like I also prefer to read EN books in the original language, I’ve too often been quite annoyed by bad translations.)
Here the language names in the respective languages:
English
Español – Spanish
Deutsch – German
Русский – Russian
Suomi – Finnish
Français – French
Język Polski/Polski/Polszczyzna – Polish
中文 (?) – Simplified Chinese
Perhaps just put these in the thread title? Tells more than anything else, I think.
Cordially, Tom