Hi, I wouldn't give it too much thought, I am pretty sure it means that the entertainers incarnate different characters for the shows.

However, I believe the expression is not properly used on that text.
They way it is used it means that the entertainers incarnate the role of an actor. And you don't normally incarnate an actor, an actor is the means to incarnate something else. Thus, it most likely means that the entertainers become actors as a means to incarnate other roles, like the ones you said, the floer, the moon............