It needs some extra valves to switch the flow of coolant around, but yes.

In the same way that an electric motor and a generator are the same thing.

Some refrigerants are more suited for cold climates, some of which require very high pressures.

I think they mean "air exchange" (split AC) vs "heat pump" (dig into the earth to draw/eliminate heat). Not saying that's the right definition though. I am guessing at an auto-correction of what they meant.