How do the hypnotizing glasses in the Incredibles 2 work? Do they work like possesion, Harry Potter-style? (Meaning they allow the glasses' controller to manipulate them like robots) I thought so, because the wearers' have no recollection of what happened to them while they were wearing them. But in one scene, a superhero clearly looks into the controller's screen face to face and gives him the details, implying that they are not like robots, and the controller does not know all the details of what's surrounding the controllee. So how do the hypnotizing glasses work? (Other possibility - like Georgina in ASOUE. But that doesn't work fully either.)
I think you have the basic gist of it correct. From what I saw in the film, the goggles hypnotize the wearer, which allows the "Screen Slaver" to give instructions to those being controlled. The screens seemed to work both ways as well, giving a live feed back to the controller.
So while, orders could be given, i.e. "Go capture this person", and what the wearer sees the controller sees, the "Screen Slaver" did not have full control over the actions/movements of the wearer. Considering that numerous characters fall under control at the same time would make it impossible as well (Left hand is player one, right hand is player two, okay now I have to use my foot for player 3).
Skooba is correct. Normally, Screenslaver just gives instructions to the people controlled. However, there is one instance where that seems to not be the case.
Right after Elastigirl discovers ...
the real Screenslaver,
Screenslaver states that
"He gave you a pretty good fight. I should say, I gave you a good fight through him."
This implies that Screenslaver was personally controlling the person who was fighting Elastagirl in a manner similar to "possession", even though Screenslaver does not do so in other instances.