While it's generated by AI, the work behind it isn't just that. First, I manually redraw the original icon so the AI has a better reference. Then, I generate it using the appropriate prompt, and once I have the image, I usually tweak it to make it look better. This includes increasing the brightness, editing out some parts I'm not happy with, and so on.
I'll be adding more icons and posting the original drawings in the comments. I hope you find them both useful.