For corrugated plates, depending on the direction of the corrugation, the plate exhibits significantly higher bending stiffness about one axis compared to the other.

For example, when the corrugation runs in the direction of local X, the bending stiffness about the Local Y axis will be much higher (because of the shape of the corrugation),

To test it, we have created a model containing three cantilever plates. The first plate group is isotropic, the second plate group has corrugation running in the local X direction, and the third plate group has corrugation running in the local Y direction. All beams are subjected to a vertical joint load at their tip, leading to bending about the local Y axis. The vertical displacements due to load are shown in the following screenshot:

As we can see above, the second group with corrugation running in the Local X direction shows smaller displacements (i.e higher bending stiffness). On the other hand, the third group with corrugation running in the local Y has almost the same displacement as the isotropic plate. In other words, the third group has nearly the same bending stiffness about the local Y axis as the isotropic plate - which is expected.