There is really nothing complicated for that grass.
I bought this pack: https://store.speedtree.com/product/backyard-grass-ue4/ and used the “desktop” version of it. It’s easy to replicate that speedtree grass, I bought it because I was too lazy to find and work on a decent grass opacity texture (shame on me =P). What I get inside UE4 after importing the model is a cluster of planes with the grass material (diffuse, opacity, normal and a speedtree color variation chained with diffuse).
The only real advantage of the Speedtree model is that you’ll get the wind simulation (which I’m not using, btw, because wind must bee very strong to visually affect short grass like that in real life). After importing this, I distributed it over the surfaces with the foliage fill tool. The individual planes are very noticeable in low density distribution specially with short grass like that. There are two ways to avoid that: 1) increasing foliage density and 2) matching the surface color with the grass color. You must combine both if you don’t want to increase the density too much. Matching the colors is also important if you want to limit the distance of foliage rendering to improve performance.
I didn’t like the Speedtree color variation node, so I got rid of it. The variation of my grass comes from a blend between the blades texture and a macro texture (same from the surface) with world coordinates. Here are the instructions for that: Foliage color variation - Rendering - Unreal Engine Forums
I’m also using that new 4.7 foliage shader. It’s not visible in those pictures, but there are some translucency on those blades when the light comes from behind them.