Yay!
I didn't handle that directly but basically rotate the ground and objects that lay on the ground by 45 degrees. For the object standing on the ground, you don't need any rotation. Pivots for standing objects should be at their bottom. Standing moving objects should move relative to the ground rotation. This way you got that depth effect by moving the camera upward and backward on the ground. The moving objects will need some sort of dynamic adaptation for the order in layer to always appear in the right order.