In theory, it would certainly be possible to use Microsoft Azure voices
with an addon, however I'm afraid it doesn't make sense at all. There
are several reasons for this:
1. these voices are not installable, but always run online. You would
have to make sure you always have an internet connection.
2. let's assume that you have a permanent internet connection. Even
then, depending on your internet connection, you would have a very high
delay compared to the locally installed voices. Even if you had a very
good internet connection, the response would most likely still not be
high enough to work quickly and efficiently. Everything the voice is
supposed to say is calculated in the cloud and then played back. These
high quality voices that are processed in the cloud were not designed
for such deployments.
3. You can't just buy the Azure voices and use them at will. In the
Azure cloud, everything is charged per performance, compute cores,
queries, word count, etc. So depending on how you work it could get
I hope I was able to explain it in an understandable way. If something
is still unclear, just ask again.