How can I create this fade effect / texture, without decals?

[SimplyBamb000 (SimplyBamboo)]

I’m trying to achieve this fade effect:

Currently, I’m using decals of a fade texture on all sides:

This works visually, but I know it’s not performant.

My main goal is to recreate this effect without decals while still being able to change the color of the fade.

Does anyone know a more efficient method? I have tried other things but nothing seems to work well atm.

[Tavikron (Octav)]

You could use vertex transparency, but transparency as a whole is not that optimized for Roblox

[SimplyBamb000 (SimplyBamboo)]

I believe this is more optimized than using 4 decals, ty. This is also a very easy way of doing this because earlier I was doing some weird uv texturing.