He isn’t a good defender. He’s in the same category as Upamecano and Konate - defenders from Leipzig who somehow command ridiculous money but are just a bit meh. Konate and Upamecano at least have the physical attributes to recover from mistakes.
He’s technically decent but he’s not particularly quick, not particularly tall or good in the air, not overly switched on and isn’t great 1v1. I don’t personally think he is a left back. Watched him play left back for Croatia against Spain at Euro 2020 (in 2021) and he was a car crash.
Maybe unfair to judge him just yet, but it’s an odd signing when Ake is absolutely fine (and would benefit from playing consistently). Seems a lot of money to spend on a player who is just OK.