Are object1 and object2 really different objects? Or are they two instances (copies) of the same object?
With two different objects there should be no problem accessing their instance variables in the same event.
If they are two instances of the same object, then there is a trick you can use -
say you have a sprite Circle. Create a family CircleFamily with just this sprite.
Then change your event to this:
Circle overlapping CircleFamily ...
Inside this event you will be able to access both instances that are overlapping - one using "Circle" name and another using "CircleFamily".