Below is a list of all puzzles present in the Resident Evil: Revelations 2 and how to solve them.
Artificial Eye (Claire/Moira)
In order to obtain the Artificial Eye, the player has to pick it up, which will trigger the spikes in the ceiling to come down. Once they are low enough, the statue to its side will be destroyed and the Processing Plant Key will drop. When this happens, place the eye back onto the unharmed statue and pick up the key.
Glass Eyeball (Claire/Moira)
After the above, the Processing Plant Key needs to be used at the room on the first floor of the factory. This room has multiple lasers that will shoot and instantly kill the player if they try to approach the Glass Eyeball. To solve this, Moira's Flashlight can be used to show the correct path to take to the eyeball.
Liver Replica (Left) (Claire/Moira)
To obtain the Liver Replica (Left), the player must be Claire and shoot at the hook above the meat so it falls onto the grinder, then switch to Moira and interact with the lever on the other side so more can spawn for Claire to shoot.
Gates at fiery factory area (Claire/Moira)
The gates at the end of the Food Processing Plant area with a timer serve as a trap, all gates but one will kill the player, and the correct choice is not always the same. To the right of the gate is a Partner Action Button prompt where Claire will help Moira get to the top and past the gates, from there, Moira can see which gates have spikes on it and which don't, switch back to Claire and open the gate without any spike.
At the start of the episode, Barry and Natalia will end up at a section with cranes, one of the medals is related to completing this segment in only three moves.
To do this, get a character to the first platform, then move the lever next to it, then switch characters and climb the ladder to the right of the platform and stand on the area that moves alongside the platform. Then switch back to the first character and pull the lever at the location with a "3" on it. Switch characters again and go to the right side and drop down the ladder, then switch back to the first character and climb up the ladder. Get one character to stand at the same location again that moves alongside the platform while the other goes to the other side and pulls the lever at the location with a "5" on it. Swich characters one last time and drop down the last ladder.
The Shotgun TAP194 is also present in this area, to get it, do the same as the above but once the lever at the location with a "3" on it was pulled, have Barry at the platform on the first floor and Natalia go to the other side and pull the lever at the location with a "5" on it. As the platform is making its way there, make sure to have Barry in control then walk towards the location with the Shotgun as you pass by it. In order to get Barry out of there, have Natalia pull the lever with a "4" on it which is next to "5" twice, then pull "5" again, then control Barry and walk to the platform as it's moving by.