The problem is that of course the list would change so it can't be in a container.
Firstly, it's NOT one of the sprites on which I check for overlaps that are being dragged. The sprites on which I check overlaps stay still. Other objects that are on top of those sprites are being dragged.
Here, let me try ot make it more intuitive
Imagine a 10x10 grid of square sprites that overlap their neighbors by 1 pixel. I have an object on top of one of those sprites somewhere in the center of the 10x10 grid, and I want to be able to move the object a radius of N. When the player drags the object, the radius of N sprites is highlighted to let the player know where they can drop the object. Ideally a distance expression would work for this above example, but instead of a 10x10 grid, teh sprites are in this case not necessarily equidistant as a function of their range (N) from the object (e.g. instead of physical distance and range, if you think of a network of sprites with varying sizes and locations of overlap, what i want to get is the distance of radius N in connection space)
When I drop an object, the sprite associated with it would change to the sprite on whcih I dropped it, so if I made a container that wouldn't work. Furthermore, it is possible to drop multiple objects on the same sprites, so although each object is associated with a specific sprite, the converse is not true, such that each sprite is not associated with just one object, it could be associated with multiple objects.