El Libertador achievement in Civ 6

Simple.

Hotseat mode with Gathering Storm Ruleset and and starting in the Ancient Era.
Select Simón Bolívaras your leader and pick anything for your dummy Civ and change it to Human and delete all others by choosing Closed.

Once the game start settle immediately. When it's the dummy's turn simply delete the settler and you'll win automatically and the achievement will unlock.