It's pretty fast. I play on hard for most games, and here that means you're reasonably lethal and enemies hit hard. There are encounters i've failed where I had to have an explicit plan to deal with the enemies prior to engaging (though I was probably also slightly under leveled) because of how fast the combat can be. It's not a perfect game, but they capture the Harry Potter "fencing duel" aesthetic of wand combat pretty well.

Overall, while I'm not a crazy Harry Potter fan (I've read all the books, but was older than most when I did, and have never actually sat down and watched any of the movies completely), the charm of the setting really shines through across the board. The writing, the implementation of Hogwarts and some of the other locations, the gear (while I wish it was more RPG-feeling in terms of stats and perks, it nails the look), the combat, everything from top to bottom. It's pretty clear the people who worked on the game are either big fans of the source material (movies, specifically) or at least did their research, because it completely nails the feel of the IP.

The downside is that that crazy densely packed setting is really demanding to implement, so there's a lot of loading (it tries to do it transparently, but if your hardware can't keep up you get spinning circle delays on opening doors) that has to happen. I didn't think it was bad overall in my 30 hours on steam deck (though traversing Hogwarts with 3-5 second door loads a couple times in quick succession can be frustrating), but tolerance for performance varies.