Like JonasO has already said, I don't think you can really get that same style of grass down into a single tile. There's really nothing wrong with that, it just makes it a little more complex to make the maps!
So the whole grass effect they have going there really relies on using a single midtone as the majority of the "pattern". When in use you'll want that color to compose most of the grassy area as well.
To demonstrate, I made four quick tiles:
One flat midtone tile, one detailed single-tile, and two tiles meant to be used side by side.
Here they are in use (I think I cheated a bit and flipped some of them horizontally):
And taking it a further (cheating) step forward, I thought it could look better but didn't feel like making any more proper tiles for this so I went ahead and drew in some more variety on top of the previous example.
Just for fun I also did some stone path tiles to see how they'd look with this - again, I kind of cheated and drew stuff on top, so these aren't really proper tiles: