Sanity: Descent Into Madness gives you a sanity indicator using a brain icon. However, why would you want that? If we're being realistic, you wouldn't have any way of knowing if you were going insane until the very last moment! This resource pack removes both the tendrils and the brain indicator so you can play without knowing if you're going insane.
Should work on every version of the mod, but it's only tested on 1.20.1.