Iam deep-diving into the Midjourney Alpha website world of style referencing. It is more difficult to do on a Discord server, but not impossible.
I have used my own artworks as image references for a good while now, but that was generally taking an image and getting variations on the theme of the image. I might paint a boy in a beach scene and create variations on that scene. Most would still have a beach and a boy.
Now, with style referencing, I could create an image of an astronaut on the moon, but it would have something of the style of the boy on the beach.