That the question i really dont know , but people say yes
what did they do to it?
There is no nerf apply to Spr, but there is a nerf in Priest Tree for battle league where Stone Skine scales Spr x 0.5 instead of Spr x 4, so full Spr builds are no longer available for people looking for Arena.
Sorry, but is this Stone Skin nerf already implemented on iTOS? I know that some nerfs on plague doctors and cryos are not present right now
It is not present yet, it is just for Team League (Competitive Arena).