"Non-standard" language settings for Voice Assistant?

I am using the Wyoming Microsoft TTS add-on (GitHub - hugobloem/wyoming-microsoft-tts: Wyoming protocol server for Microsoft Azure text-to-speech), using which I could use the multilanguage voices available on Azure, especially the ones from OpenAI. These voices have much better quality then the “regular” language dependent voices. These multilanguage voices show up however only under US English, hence I cannot use them in my own language (Hungarian).
Would it be possible to use a voice that is not the language of the Voice Assistant? Can I create a custom config file for example? I could not find any config files for the Voice Assistant, so not sure if it’s possible.
Thanks!