I don't know if it's as much a Mangekyo counter as it's a Tsukuyomi counter. I think it would be a little to powerful if it could counter every Mangekyo ability. To me it seems like Tsukuyomi is the only ability that is a threat to Naruto. Amaterasu could be negated by narutos speed to avoid it and the fox-armor to not allow it to touch Naruto directly. And Susano is powerful but i think foxmode will beat that with a few hits. Tsyokiyomi however will be instant and Naruto is no good at fighting well if he have to worry about it by not looking. And if it hits, Naruto don't have the nine-tails like Bee have eight-tails so he can't snap out of it. And that's the crows only function. To negate it before it even hits. I would have a big problem if Naruto had a power to negate every sharingan related ability. This scenario however i have no problem with at all.