Board Thread:Versus Debates/@comment-25643824-20161223231153/@comment-35622277-20161224054928

Ninjachris wrote: How can sasuke possibly know what is naruto's shadow clone limit. besties share secrets

Since Momoshiki absorbs ninjutsu through the Rinnegan in his hands, I'm pretty sure he loses this ability when he enters his rock avatar as he is located inside of it. So if Naruto and Sasuke both enter their respective Avatar modes (individually, while alone), it's an automatic loss for Momoshiki.