The whole process actually takes place over two shortcuts. I abstracted away the process of preparing images (giving them titles, compressing them, etc.) as I wanted the shortcut to be flexible enough to be able to do that work on images either from the Photos app or from the webpage I’m linking to. For reference, that images shortcut is called Prepare Blog Image.
This article was a huge inspiration to me for automated my posting. I’ve changed his shortcut quite a bit but I appreciate the effort that went into this.