How to use specular output in material editor correctly?

Hi everyone, I am using Unreal Engine and Quixel Megascans. and I am wondering about the specular node in the material editor.

Notes:

  1. I know that a specular node in the UE material editor is used for the IOR value.

  2. I also know that It’s only used to tweak the dielectric surface (not metallic)

  3. I also know that some people leave it as its default value (0.5).

But I really want to manipulate this value using Quixel textures. So is there any way to get the IOR map from specular or any other map? If there is a way to make a function for it that can convert the available Megascans map to IOR in UE material editor then please guide me :).