Board Thread:Versus Debates/@comment-31171723-20170128170340/@comment-35622277-20170130230656

No, the Yata Mirror blocks physical attacks as well. Although in all fairness we haven't seen how much the mirror can actually block. I seriously doubt it could block the force from a Susanoo. Like Itachi himself even says, every jutsu has a weakness, including his own. We also don't know if can seal Susanoo, let alone pierce it to actually seal it.

It is said to be able to almost pierce anything, but like Orochimaru's Sword of Kusanagi (which this is a variant of) could not cut through chakra shrouds, it would probably useless against anybody with one (e.g. Perfect Jinchuuriki, Anyone with Susanoo).