What I believe is that in something like Blender the app would store each blade as it's own geometry. The way that I would do this in OpenGL is to go over each blade in a render pass. Would it be easier to add them as child nodes. Though I need to know how to make them 2 sided. or use a bunch of shader passes, which I don't know how to do. I could use something to say where the grass patches are.
What would be the best way to create grass from a few meshes?
create alpha mapped planes something like these https://sketchfab.com/3d-models/grass-patches-6952780b80594a31aab2dedf7249a47a