To get all five Minikits in the Starkiller Queen level in Episode VII – The Force Awakens in Lego Star Wars: The Skywalker Saga, you’ll need to play the level on Free Play. Only one of the Minikits can be obtained in Story Mode, and even that one requires you to disguise Finn as a Villain.
The locations of all five Minikits in Starkiller Queen are as follows:
To get the first Minikit, you’ll need to be playing in Free Play, so that you can switch to a Scavenger character. Above where the sniper bridge is (or was, if you’ve completed the Rug Pull Challenge), there are places on the wall where you can attach nets, so attach some nets there. Next, grapple up to the ladder, climb it, then clamber across the nets to reach the Minikit.
The second Minikit also requires a non-default character, so you’ll have to get this one in Free Play too. At the end of the corridor where you got the first Minikit, there’s a door that only a Bounty Hunter can destroy, so switch to a Bounty Hunter and destroy it by shooting each of the four gold locks. Switch to a Jedi or Dark Side character and lift the last crate on the right into the crusher. Now activate the crusher by turning the two handles with a character each. Finally, drop into the crusher and build the Minikit from the debris.
You can get the third Minikit either by using a Villain character on Free Play or by disguising Finn as a Villain on Story mode. Go down the westernmost of the three corridors that lead south, then turn right into another, shorter corridor. Use the console outside the last door on the left, then throw a grenade inside and build the Minikit from the debris.
For the fourth Minikit you’ll need a Dark Side or Jedi character, so this one’s Free Play only. Go to the center of the southern edge of the map and cut open the door here to get to the Minikit inside.
Not only will you have to be playing on Free Play to get the fifth and final Minikit, but you’ll also have to capture Captain Phasma so that you can use her to enter the systems control Room in the center of the map. When you enter the room, turn right and smash the machinery in the corner. Build a console out of the debris, then use an Astromech Droid to activate the console. The model Starkiller will open up and the Minikit will pop out of it. Get all five Minikits to unlock the Starkiller Base (Micro).