does it show for other players or just you?

Obviously it also shows for other players
What's the purpose of making it into an item if it's only for you to see?

It's not actually shading, it's an immitation of an old toribash function using 3D objects. So it shows for everyone as long as they have3D objects turned on. You can check how it looks ingame using /dl Tertywerty and then /lp 0 Tertywerty.

k thnx