There is no option for turning off fog for specific objects in URP Forward/Forward+. I have looked for solutions and found nothing that worked. So I copied the HLSL code for the URP-LIT material and removed the line #pragma multi_compile_fog to see if this would omitt any fog passes. It woked very nicely in both the editor & build.
Does anybody know of any bugs and errors? Seems odd this feature is not included in Shadergraph or else.