"Common Ground" is now written for a closed group in order to improve the story before it is released to the public for the first time.
If you are interested, here is the synopsis:
"Meet a modern, urban and advanced Equestria. Where there is no kind of princess. Not even Celestia and Luna. But if there are no princesses, what happened to them? Well, they were born and raised as earth ponies. But currently, in the midst of so much social and emotional noise that life in the city causes; Celestia, a pony in search of restarting her life., and Luna, a pony with her head among the stars, are destined to meet when they both witness an important event."
At the moment it will be released first in Spanish, but I hope that in the future it can be published in English.