Anno: Mutationem is a weird game. First of all, it looks amazing. They totally captured the cyberpunk aesthetic. But in my opinion, the gameplay is just 'ok'. It isn't bad by any means, it's just generic.
The game has two different types of gameplay: 3d exploration, and 2d beat 'em up. And the two don't mix. When in the exploring areas, you can wander around wherever you want and talk to NPCs. But once you enter a combat level, you're locked in a 2d plane for a beat 'em up game. The entire game basically alternates between these two modes, until you reach the latter part of the game where it's all action.
Overall I enjoyed the game but I was obviously playing it for the cyberpunk aesthetic, which is where it shines. Otherwise, the exploration is limited to small regions and the combat is fairly repetitive. Neither are bad, just small in scope.
Here's a trailer. You can get it on Steam, Switch, Playstation, Xbox, wherever.
I had 10.7 hours of gameplay and HowLongToBeat says the average is ~11 hours for people who don't spend much time in the side quests, so that seems about right.