SpeedTree 8 shaders incorrect lighting when not using SS

The same tree, left is using a standard surface shader, the right is using SpeedTree 8 shader without a Subsurface map.
I don't know how performance heavy SpeedTrees implementation of subsurface is, but I would rather have it disabled and behave like the shader on the left, 1 for performance and 2 I haven't been able to get good results with it anyway.



Unfortunately the billboards also behave like this.

Is this a known issue? Or expected behavior? If this is expected it would be great to be able to not use subsurface at all and have correct shading.

 

Did you figure it out eventually?

 

SpeedTree doesn’t seem to be supported anymore by Unity, or the SpeedTree team.

Their shaders don’t even work in URP at all.