Open ANSYS Help, go to Mechanical APDL > Command Reference and read the ESYS command.

That has some useful information. I used it to set the randomly oriented element triads in the post I linked to above, to a global or defined csys.

You need to set it to the I-J direction of the element, but only if the elements were meshed so that the I-J direction is uniform.

I can't help you more that this. Maybe some ANSYS staff can give you more help.