I finally got this recently and it's pretty great. It's like Breath Of The Wild and Dark Souls had a Pokémon baby with a polygon deficiency. Some things about the game that stand out, whether you like or dislike them are:
-Your Pokémon can no longer hold items
-Once your Pokémon masters a move it will gain the ability to use that move in either an "agile" or "strong" style. Using a style takes up twice the PP. Agile style hits less hard but moves faster, sometimes giving you an extra turn. Strong style hits twice as hard.
-Because this game takes place in ancient Hisui, there are no gyms, and some Pokémon have different types or appearances.
-Almost every NPC hates but tolerates you at first. They warm up to you when you prove yourself to them somehow. They're also terrified of Pokémon.
-The town you live in is literally built up around you, with your influence.
-You're threatened with death repeatedly throughout the game. A LOT of the NPCs pretty much tell you that you have a death wish for interacting with Pokémon. It's also mentioned that Pokémon have killed or maimed humans in the past.
-Wild Pokémon attack YOU, the player. Encountering a Pokémon does not bring out your team automatically. They can attack you and if you're hit too many times you will be knocked out and brought back to town by the Medical Corps.
-There are full-on boss battles with Pokémon Lords where you will only survive by learning their attack patterns, dodging, and throwing stuff at them until you get an opportunity to fight them using your Pokémon. They're pretty forgiving though as if you die, you get an option to start again while keeping some of your progress.
These are just some of the differences. I'm really enjoying this game so far but it's definitely not for very young audiences or for people who don't have good hand coordination yet. Your in-game character is 15 which is probably around the target age for this game. If you're like me and you want a decently challenging Pokémon game that's nostalgic and modern at the same time, this is perfect. I also really appreciate the story's theme centering around changing times, different religions and clans learning to share and protect their homes, and respecting nature.