When wearing armor from any mod, the game crashes immediately, except for vanilla Minecraft armor
Whether it is 3D or 2D.

game Version: 1.20.1
Mod version: ismah-forge-1.1.0-1.20.jar
forge version : 1.20.1 - 47.4.0

Crash file :

crash-2025-04-21_02.38.10-client.txt

This crash is apparently using armor from the Epic Knights mod and a pre-2.0 version of ismah as this mod was tested in 2.0 and works perfectly.