All of them.
The Witcher 3 - Doesn't hold a candle to the second game. Too much crap to find on the map, and overall unfocused. Made characters from previous games worse and didn't care much about the story of the second game. It's a good game, but not a masterpiece- I'll give them credit for their expansions which blew the main campaign away.
Super Mario Odyssey - It's a good game, but neither the best Mario game or the best platformer of the generation. Boring sandbox design, and not many real challenging platforming sections. Overall a disappointment after all the hype I read about it.
God of War - In my opinion, it butchered the series and it butchered Kratos. Combat wasn't fun and I miss my cool boss battles. This is not what I want from the series. Game is decent at best.
Red Dead Redemption 2 - Doesn't hold a candle to the first game. Mission are not as good, and I don't like the open world as much. Gameplay is still from the PS2 GTA era.
Resident Evil 2 - "Look how they massacred my boy"
Zela: Breath of the Wild - One of the worst Zelda games. Am I playing Hyrule's Creed or The Legend of Zelda? Breakable weapons was also a pita.
Hollow Knight - Other than the art and music, there's nothing good about this. Worst, being the absolutely useless map.
The Last of Us 2 - Make a movie already.
Uncharted 4 - Doesn't hold a candle to Uncharted 2.
Bloodborne - Cool atmosphere and fun combat, but I'll take Dark Souls over this every day of the week. I'd probably like this more if it got a PS5 upgrade. It isn't bad at all, but there are better action games.
Overwatch - Paladins is a better and less toxic game.
Sekiro: Shadows Die Twice - Parry, parry, parry, win.
Super Smash Bros Ultimate - Just because it has a big roster doesn't make it good. Have a smaller amount of playable characters, and do them right.
Metal Gear Solid V: The Phantom Pain - The gameplay itself is fun, but the open world is empty, story's crap and Quiet is an embarrassment.
Divinity: Original Sin 2 - The way the number bloat works ruins the game, and I'm saying this as a big Larian fan. The way they implemented the shields was also shitty. This isn't Mass Effect. If you want to get into Larian games, play the first game.
Celeste - Shit.
Monster Hunter: World - Overly convoluted and add to that boring monster fights. I'll play the portable ones, thank you very much.
Persona 5 - There are many good things about it, but they also fucked up. Too easy on all difficulties, boring party members and the game tries to send a message over and over, but contradicts itself on every turn.
Inside - All of these devs games are super overrated. Edgy platformers that don't even control that well.
Animal Crossing: New Horizons - The most pointless game that also sold gangbusters. The developers must be laughing on their way to the bank. A more meaningless game, I cannot find.
Undertale - Pretty decent rpg, but it's nothing more than that.