I think it would be such an advantage to an independent production that I can live with a robotic sound, I could add a robotic environment with robotic characters then.

I know the window's narrator, but I fear it has license issues.

Transform text-to-speech plugins for gamestudio? Where?

EDIT:

Let's cut it to pieces:
What about the very basic: text-to-speech?
The other features seem more or less possible with things like the FMOD Wrapper for lite-C?