User Configuration > Administrative Templates > Microsoft Word 2016 > Miscellaneous
User
HKCU\software\policies\microsoft\office\16.0\common\research\translation
This policy setting allows you to prevent online machine translation services from being used for the translation of documents and text through the Research pane. If you enable this policy setting, online machine translation services cannot be used to translate documents and text through the Research pane. If you disable or do not configure this policy setting, online machine translation services can be used to translate text through the Research pane.