yes thanks for the screenshot your material nodes are exactly right ! what is missing is at the bottom where it says: blend mode: blend_opaque change it to blend_multiply or blend_modulate not sure what its called anymore in the old unreal there was also a blend_darken but i think they kicked that out :)
i think the vertex color shadows for the leaves are really not working. what i would do is make the leaves all be a separate object they have their own material anyway so you wont be gaining any extra draw calls by doing this. than set that object to "not" cast a shadow. instead build a little decal below the leaves and…