This Seeking Tech guide will show you the best farming spot that can be found near Virga Island.
Use the following video as a reference:
To get to this location, get to the save point near the top of the Spire of Blind Faith. You then need to backtrack down one floor to the skeleton enemies.
There is one level 50 enemy that you may not be able to defeat in the overlord until you reach level 53. In that case, you can run away from it while.
For the rest of the skeletons, you should aggro them by running past them. You can then turn around to start attacking them. Make sure you are using the Merchant or Tycoon Archetype to get a lot of money.
In just a minute, you will get 1K EXP, 600 Archetype EXP, 3K MAG and 29K in cash.
To respawn these enemies, you need to use the save point to travel to Akademia.