Cities: Skylines II

Currently, the easiest and possibly only way to get this achievement is to go into the editor and place an object (via the house icon at the bottom). Then select the object from the "Objects" section on the left, click "Duplicate Template" on the bottom right to duplicate the object. Now you just have to place the duplicated object and click the save icon next to the copy that has now appeared in the Objects list on the left. This should make the achievement pop.