Does Microsoft Translator store the content for translation on Azure cloud? Is there an option to configure translator to ensure data doesn't go out of the corporate firewall ?
You can request no-trace, meaning Microsoft will keep no record of the translated content: https://www.microsoft.com/en-us/translator/notrace.aspx
The corporate firewall still needs to allow accessing an outside location.
For IP-filtered firewalls: https://cognitive.uservoice.com/knowledgebase/articles/1128352-api-translator-text-microsoft-translator-with-i