If you send /voices you can pick from multiple voices.
Right now it only shows voices in English, but you can send the secret `/setvoice <voiceName>` with an Amazon Polly[0] neural voice and it will work as well.
The only downside right now is that I don't auto-identify languages, so if you set it to Dutch, but ask a question in English, you'll get a response in English with a very Dutch accent haha.
P.S. And yes @aero-glide2 is correct that you can toggle between Telegram's audio/video inputs by tapping the camera/microphone icon. – Right now MarcBot only supports audio inputs.
[0] https://docs.aws.amazon.com/polly/latest/dg/voicelist.html