Unlit shading model is missing..?

Seems like the shading model for Unlit is missing in material expression options.

It is quite important for me to make optimized clipping function for Archviz.

Basically I need to make the inside of the mesh Unlit when I chop it off (There’s other way using Normals but that compromise shadow quality)

Wonder if there’s any solution on feeding Unlit to one of those node?

I think maybe is missing because of the material domain you’re using.

You can’t use unlit when using the shading model from expression mode.

Is there any reason for this? Doesnt make sense at all to me

Ive come up with a workaround for my case which is inspectable items in a horror game. Even if you pick up a letter in the dark I want it to become evenly light so the player can read it. In this case I change its lighting channel to 3 (unused so it recieves no light at all). Then I set the emissive color parameter on as you would with a unlit material.