Here is the full list of all 8 Playing History 2 - Slave Trade achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Play the "memory game"
Decide what to do with the lack of food
Find out if Akim has scurvy
Play "Slave packing"
Find out the travel time for your journey
Negotiate slaves with the chief
Play "Find 10 errors"
Talk to Wallace about the trip to Africa