Is he though? I'm yet to see this in the English game, and plenty of players have arrived from other leagues and simply not been a good fit.
He hasn't scored or assisted once, in an attacking side where he often is playing pretty high up the pitch and he was signed to add a creative drive to your midfield. That's pretty awful, I get that he's been in and out of the team but he's had a few starts and a number of sub appearances where you'd have expected him to make a crucial contribution at least once. I get that he's a central midfielder and that isn't his primary job, but he did it pretty well at Leipzig and it's not like he's anything like a Kante type, he's very much an attack minded midfielder.
So far I haven't seen anything to impress me. Certainly I see him as the worst of your summer signings, and I expected him to be the best to be honest, since the hype around him was pretty significant. Of course he should be given time to settle and can't be rationally judged so quickly, but thus far I can't see how he's been anything less than a disappointment.