Minikits in order as they appear:
In Chamber 2. There are two doors behind the blue colour platform. Use Wyldstyle (Relic Detector) to detect the boomerang slot. Then take Batman (Boomerang) to shoot the boomerang. Climb up with Acrobatics and grab the Minikit.
In Chamber 3. Use the Portal 2 gun to get to that little room underneath the path.
In Chamber 3. There is a golden Vent at the water level. To use the Laser, your laser needs to fly. Either a plane or a flying Minifigure with the Laser ability.
In Chamber 5. Get behind the laser bars right of the end of the level with the Portal 2 Gun.
Chamber 5. Follow Wheetley into the corridor. There is a little island in the water. Fly over, use Relic Detector and then the Boomerang to get the Minikit.
In Chamber 6. In the back, there are some pipes to use the Drone.
In Chamber 6. Use the pink portal to get to the room underneath and use Hacking. The door opens and you get the Minikit.
In Chamber 8. User Super Strenght to rescue the Adventure Core.
In Chamber 8. Use the Portal 2 Cube and the Portal 2 Gun to get the Minikit at the far right.
In Chamber 9. No special ability required. Use the shrinking ability with the pad and go through the pipe to push the button.
In Chamber 9. Use the Drill ability at the far right. Then just pick the Minikit up.