Not sure how difficult it would be, it also depends on the following: Would you expect it to affect the ordering in the configure page of the behavior (the page where you choose values of non-hidden attributes, when you attach the behavior to an actor/scene)?
I think it would be more natural if the order in the configure page would not be affected by the sorting, since you normally would want them to be sorted there by in a certain way, like the most important attributes on top, and related ones next to each other.