This page of the Resident Evil Village guide contains a list of all files / documents you can find in the Heisenberg's Factory, the last location on the main map. The following list will help you explore all the factory levels in 100%.
Development Note 1
The notes on Soldats are in a room on level MB4 of the factory, where you will also find a suitcase with the Cog Mold item. They are lying on the desk.
Development Note 2
You'll find notes on more varieties of Soldats shortly after you start exploring level B2 of the factory, specifically after you climb the Grinder Shaft. The notes are lying on the table.
You will find the note in a room on floor B1, which you will reach just after using Heisenberg's Key next to the elevator. It's about a Prototype Sturm opponent you will face in the adjacent room.
Heisenberg's Diaryl is in the control room, which you will reach right after defeating the Prototype Sturm boss on level B1.
The laptop is in the Scrapheap area on level B5, which is the same area where you will meet Chris and find the mini-tank to use in the duel with Heisenberg.