Hi all,
I have only recently finished the CG Master Academy course; Hair Creation for Games by Johan Lithvall:
https://3dclassroom.cgmasteracademy.com/elective/2065
The hair is build from polygon cards and has about 40K triangles and is a screenshot from the Unreal Engine using EPICs latest hair shader.
You can also find an article about the process of creating this on 80 Level.
https://80.lv/articles/techniques-for-game-character-hair-creation/