We have purchased Office 2016 licenses and want to use the software in a multilingual environment at our turkish business location. Do the available licenses cover this scenario?

Yes, you can use Office 2016 in a multilingual environment and switch between languages at your will, if your licenses originate from a volume license agreement. As of version 2016, the Mulit Language Pack is no longer a Software Assurance benefit, but a part of the Office suite.

Source: Volume Licensing Reference Guide_Microsoft_Office_as is 2017-06-21