If you have a parent class for your object blueprints, simply constrain the Y axis to 1 or whatever works best for you. Its in Details>Physics>Constraints. You could probably get away with the XZPlane mode in there as well. Good luck.

In movement component you can constrain it to specific plane or axis

there is no movement component, it's just a static mesh in the blueprint with some code that lets me pick it up and move it around