Hi, in the conditions of your objects, you can check if they are in between two angles, then you can set if they must be mirrored or not :
If between 90° and 270° : Set mirrored
Else : Set not mirrored
Edit : since you're not using Set Angle here is a similar solution, use the System Condition "Is Between Two Values" and compare your object behavior angle of motion the same way I explained in the above example