Vosk provides speech recognition in Unity with standard Vosk libraries as Unity is essentially C#/Mono scripting environment. For now it is not an official support, there are few external projects, but we hope to integrate Unity into official repo soon.

See for details:

https://github.com/alphacep/vosk-api/issues/691

https://github.com/Yeti47/Vosk4Unity

https://github.com/Babilinski/vosk-stt-unity