
Other characters with similar, cancellable moves – Kragg pillarless (side special cancel), Orcahop, Ranno needle charge – can all be performed with any shield/shield+button macro (i.e. parry or grab).
However for some reason, Zetter’s flip is ONLY possible if done with a shield, and strictly shield, button. Parry and Grab still execute the normal down special with a hitbox.
This feels like an oversight when compared against the examples above from other characters.

created a duplicate issue with this #1722 (oops). I definitely think this is just an oversight, would be awesome if it was addressed next patch