Simple skybox for Godot is a tool script and have six sides where you can apply texture.
Note: No sky textures is included - you can find them in internet
PanoramaSky is for hdr(cubemaps). This script allows you to construct skybox directly from six textures. I found that internet contains a lot of these single images, so this script could simplify the life for developers a bit.
Insert the Skybox.tscn to your scene and setup six textures to it, after this restart scene and the resulted skybox will shows, scale it how you like, and enjoy !