You can do it with KVC:
Swift:
pipController.setValue(1, forKey: "requiresLinearPlayback")
Objective-C:
[self.pipController setValue:[NSNumber numberWithInt:1] forKey:@"requiresLinearPlayback"]
Swift:
pipController.setValue(1, forKey: "controlsStyle")
Objective-C:
[self.pipController setValue:[NSNumber numberWithInt:1] forKey:@"controlsStyle"];
Note: iOS16+ only
Swift:
pipController.setValue(2, forKey: "controlsStyle")
Objective-C:
[self.pipController setValue:[NSNumber numberWithInt:2] forKey:@"controlsStyle"];