Here's a theory: Orb = ISBE.

Not really. Let me clarify. The ISBE is a singularity. But it can gather energy around it, similar to a snowball accumulating snow when rolling down a hill. And that gathered energy is what we would call the energy body.

Now watch the following video. Ben discovers a faint flickering dot after the orb has been hit by the missile, and at 15:57 asks an interesting question:

"Are we looking at the actual source there? The actual energy source... the thing that's navigating this thing."

So, what if that's the ISBE?

I mean, when Courtney is talking to the ETs about the drones, they always mention that they don't like to call them drones. Why don't they like that term? What is a drone?

A drone essentially is a vehicle without a pilot. It has to be remotely controlled. If they don't like to call them drones, it means that they are not remotely controlled. There is a pilot.

Could this mean that these vehicles work like bodies? You put an ISBE in, and the ISBE "becomes" the UFO?

The remote viewers mentioned these balls of energy in the "Maintaining the Death Traps" project. Could it be that the orb is the simplest form of a body an ISBE can have?