Global Traffic Management will route your requests to api.microsofttranslator.com (Translator Text API) and to dev.microsofttranslator.com (Translator Speech API) automatically to the nearest available datacenter.
If you need to force a European datacenter, at the cost of availability and latency, please follow the instructions in this article.
The Microsoft Translator Hub is hosted only in the U.S. region.
More information about Microsoft's datacenters is here.
Last update: September 4, 2017.