hydrographics/water transfer printing!! They take a design and float it on top of water, so they can dip 3D objects so they get the graphic on all edges.
(This is how you water-marble with nail polish too. Pick a few colors and put a single drop of each in the center of the cup until it’s full of color rings. When it gets tacky you use a toothpick to stick the edges to the sides of the cup. Then you can draw designs in it and stick your nail in. Just make sure you’ve put tape on the rest of your finger- or your whole finger will be marbled too.)