@hendryman The speech cli does not directly support setting the voice styles yet. You can however use the SSML with the required voice and style setting and run the command to get the required output. Here is a similar question that was answered to use the SSML with the speech cli.
Example: This SSML can be used with speech cli
<speak xmlns="http://www.w3.org/2001/10/synthesis" xmlns:mstts="http://www.w3.org/2001/mstts" xmlns:emo="http://www.w3.org/2009/10/emotionml" version="1.0" xml:lang="en-US"><voice name="en-US-JennyNeural"><s /><mstts:express-as style="excited"></mstts:express-as><s /></voice></speak>
With the command:
spx synthesize --file file.ssml --audio output ssml.wav
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