[el_isma]

I've found their system tries to guess the language of the text, but there are many languages that use the same words, and so it will speak in the wrong language (or accent, even). I hope they make a solution for this, otherwise I don't think it will be suitable for production use cases.

[JonathanFly]

It autodetects language by default but you can set to a specific one. Though you'd still have that problem on a multi-lingual input video.

[el_isma]

At least for their other offerings, you can't set the specific language:

https://help.elevenlabs.io/hc/en-us/articles/14888868300177-...

https://help.elevenlabs.io/hc/en-us/articles/14888917355409-...