This also depends a lot on the freedom of movement of your enemies, If they are restricted to a motion on one axis, you could change there movement speed on overlap at offset for a few moments and then return them to their normal speed..
This will offcourse only work if the enemies are moving in the same direction..
If they are still overlapping after a certain amount of time you could choose to change the direction anyway..
Easiest way to achieve any of this is to have a family with just the one enemy and check the families overlap with the enemy, I thought that way you can actually reference both instances..
For families you need the paid version though..