Microsoft Cognitive Services

Since OneCore has been removed, it is technically replaced with the cloud services counterpart.

To setup this service, you are going to need a Microsoft Azure account, once you have an account head over to portal.azure.com

• Click Create a Resource
• Search for Speech in the search box, and pick it
• Click "Create"
• Enter a name, this must be unique, for example, I just called mine nate1280-tts
• Pick your subscription (you may have to start the free trial, or if you have already done this, your service will be Pay-As-You-Go)
• Pick your location, I use East US, this location can effect what voices are available for you.
• Pick your pricing tier, you waant to pick the F0 Free Tier
• Pick your resource group, if you do not have any setup, click "Create New" and add a new one
• When all done, click the "Create" button at the bottom.
• This takes a few moments to get setup, once its done, goto the newly created service and click on "Click here to manage keys"
• You'll want to copy "KEY 1", and paste this into the subscription key box in Twitch Speaker
• Copy the location, and paste it in the service location box
• Click the Azure button to enable the engine and be sure to save your settings.

The free tier allows for 5 million characters per month with standard voices, and 500k characters per month for neural voices.

There is an option/ability to setup your own custom voice, but that is beyond the scope of this.