How do I transition objects individually?
I can think of 2 ways:


Film all the objects separately with green screens. Apply a keyer to each one to key out the green areas, place them all on the timeline, and fade each one in as you see fit.
Film them all together, and then manually mask out each object by hand. If the objects are basic shapes it might not be too hard, but if it includes people moving, etc., it could be tough. Then fade the masks out as you see fit.