Currently the workflow only available for the user profile, group, event, and page.

As well, will new audio post to social networks?

For the Facebook, unfortunately that was not possible is because Facebook already deprecated publish_actions user permission from their API.

And it possible autopost to Twitter and Linkedin social network but currently only possible to share a stream title on the social network e.g. User uploaded a new podcast ...

and are there any plans to create embed and sharing of the the audios?

we haven't plan this yet currently, perhaps you can submit this into our forum feature request section.