As a Liverpool fan and admirer of Klopp's gegenpress I wanted to make it better. First thing first, your players are going to get tired a lot. This tactic demands player with high stamina, work rate, teamwork and natural fitness.
Goalkeeper (SK-S): A good keeper with good kicking and throwing will do fine for you in this position. Recommended players; Alisson, Livakovic
Fullbacks (A): In my opinion, Liverpool has two of the best fullbacks in the world right now and it would be a shame not using them properly. Stamina, work rate, composure and teamwork are important. Recommended players; Tagliafico, Lazzari
Centre-backs (BPD-D): Your centre back duo must have good pace, stamina, technique, passing, positioning, concentration. They will start our attacks as well. Most importantly left-footed and right-footed duo is better. Recommended players, Romagnoli, Lenglet, Gomez
Defensive Midfielder (DLP-D): He's another player to start and control your attacks but he is not going to be involved in attacks so much. Recommended players; Tonali, Sensi
Centre Midfielders (BBM-S): They're going to get tired a lot because of pressing and going forward. Players with stamina, dribbling, work rate, off the ball preferred. Recommended players; Milinkovic-Savic, Barella, Ndombele
Wingers (IF-A): Pacey, technique, balance preferred. Recommended player; Kluivert, Sancho, Bailey
Forward (CF-A): Truth to be told, using Firmino was never easy and at first, I used him as DLF but wasn't happy with his performance and changed it to complete forward. Any good forward will do here.
Here are the player statistics.
You can see how fullbacks work
I only tested it with Liverpool but I would be happy if other people try and test it as well.
Hope you guys enjoy it.