Summary

My personal design of a 5 sets of chopsticks with customizable faces.
The facing plates can be printed with the color/effect of your choice (with PEI/PEO plates holographic, carbon, diamonds, etc...). In my design, the two facing plates have a text embedded in printing, done with a multicolor printer (Anycubic Kobra 3 in may case). That's why you have 2 files for each face (face and text). Open together in the slicer and affect color of your choice for each object.
If you don't want those facing plates, just do the ones you like. They are just simple rectangles sheets of 0.4 mm thickness (2 layers). The faces must be glued on the case (I used thin 3M acrylic double sided tape, but CA or any other plastic compatible glue should do the job).