This article was updated on June 7th, 2020
Here is a collection of different skies created using Skylum Luminar 4 new tool, Sky Replacement. These are all built into the photo editing app.
Heads up! They have a $35 discount going on right now on their website.
Also there are 3 different editions with bonuses.
January 21 Update: Luminar 3.2.0 is here!