Antisymmetry
Use the Antisymmetry node adds a boundary condition for an antisymmetry boundary. An antisymmetry condition is fixed in the plane and free in the out-of-plane direction.
When applied to an edge the antisymmetry plane is formed by the normal to the boundary and the edge tangent.
Layer Selection
Select the material layers to which this constraint is to be applied.
In the Antisymmetry node, you cannot access individual layers. Thus the selection in this section only acts as a filter for the boundary selection.The constraint is applied all through the thickness of the shell.
 
All other settings for the Antisymmetry node are described in the documentation for Antisymmetry in the Solid Mechanics interface.
Location in User Interface
Context Menus
Layered Shell>Antisymmetry
Ribbon
Physics tab with Layered Shell selected:
Edges>More Constraints>Antisymmetry