I'm actually creating a homemade assistant and the default speech synthetiser (in c#) hasn't a nice voice. I would like to know if it is possible, and how, to use Cortana voice and pronunciation?
You can see how to tune Cortana's responses via this link: https://learn.microsoft.com/en-us/cortana/skills/speech-synthesis-markup-language
And you can output text-to-speech (TTS) this way: https://learn.microsoft.com/en-us/azure/cognitive-services/speech/api-reference-rest/bingvoiceoutput
You can also change the Windows default voice to Cortana: https://superuser.com/questions/1141840/how-to-enable-microsoft-eva-cortanas-voice-on-windows-10
Does this help?