It does look too big to be a Yuan, so is likely nuclear - but don't all 093 versions known to date have a vertical sail trailing edge? Also the shape of the rudder is different, with a greater leading edge sweep.
To be honest, I'm inclined to dismiss it as fake though.
The question is why would russia want to co-develop a submarine with china for this purpose, if they already have submarines of their own for export? that will also mean the sharing of military tech.