In 2022, I created TCVS (Twich Chat Voice Synthesis) - a free and open-source TTS solution for Twitch . The app uses the browser Speech API to read user messages live.

TCVS is used by streamers who want to broadcast chat messages to all users, and also by users who want to keep up with chat without having to read messages. Messages are read in sequence and can be filtered by user.

If you're interested - check out the Web Speech API . The available voices depend on a few factors, but modern browsers should provide a large amount of voices. You can also change a few parameters on voices like rate, pitch, and volume.