Klopp has some things going under his sleeve, it will be a wasted effort if he doesn't signed any player now. However, seeing that they don't have any business in the Champions League this season, he might want to wait and observe how his boys are going to perform in the Premier League and then make some changes by January transfer period.
Liverpool signed 3 midfielders so far, they signed Dominik Szoboszlai an attacking midfielder from Leipzig, Alexis Mac Allister a central midfielder from Brighton and Wataru Endo a defensive midfielder from VFB Stuttgart and I believe they strengthened the midfield area mostly because that's the area they had many departures from this season and maybe the coach is comfortable with the options he had in other areas if not he would had seen a reason to strengthen other positions as well.
But according to the news they made a advancement to secure another Midfielder from Bayern Munich and their coach tuchel has confirmed that Gravenberch is set to join Liverpool and he wasn't happy with the situation at bayern anymore and see a chance in liverpool to fight for a place in their 4-3-3 formation and that the player wanted to leave and they've discussed with Liverpool which yield a clear out, Gravenberch is a fine player and Liverpool would enjoy him in their team.