Hey Crocopede,
One thing that I noticed when using the ‘Two Sided Foliage’ shading model when making foliage shaders, is to disable the ‘Tangent Space Normals’. Also be sure to enable the check box ‘Two Sided’.
Here is an example of how using Tangent Space Normals can change the way your overall foliage looks in game.
Fuzzy Shading as Subsurface
Here I am taking the ‘FuzzyShadingGrass’ node and passing it directly into the ‘Subsurface Color’ input.
Material Properties
Without Tangent Space Normals
Here is how I would like my grass to look.
With Tangent Space Normals
As you can see the model is significantly darker and looks different overall. Let me know if unchecking the Tangent Space Normals was a good suggestion for you, or if you are still having issues.
Cheers,