This one always has a hard time getting guessed.

#24 - A game where you play as a beetle trying to hit notes and dodge walls in a really freaky looking place.
Hint 2 - It's a rhythm game whose developers previously worked at Harmonix.

#21 - Portal

#16 - Horizon Zero Dawn maybe?

Kakadu18 said:

#23: Hint: The villain plans to destroy all dimensions to create the one perfect dimension. A bit different gameplay from previous games in the series.

Hint 2: Many fans consider this the ladt good game in the series, with later games moving away from the formula established in the first two games.

Hint 3: One of the villains henchmen in the end turns out to have had his own plans all the time and is then the real final boss. This franchise got a new entry last year.

Second set of hints.

#20:

• Following the events of the first game a civil war has broken out between the noble faction and those seeking to reform the empire.
• Divine Knights play a significant role in the war

#19

• The main character's name is quite fitting considering much of the game tackles themes such as existence and the value of life among many others.
• Technically, the first game in this series was released on the PS2 in 2003. It had five endings, one of which led to a direct sequel, and another that started a different series of games, in which this is the second game.

#18

• One of the main character's name is different in this game than in most of that character's later appearances.
• Although it doesn't seem like it, you don't actually meet the game's main villain until fairly late in the game.

#16

• All life on earth ended almost a thousand years ago.
• Not just humans and animals, but all biological lifeforms, though they were later brought back.

#23

• The doors between some levels in this game look delicious, being made out of things like Watermelons and Lemons.
• It's an origin story of sorts, and features locations from previous entries in the series. 
• Despite the origin nature of the game it's actually the fourth mainline entry in its series, though it isn't numbered.
• It's a colourful and lively platformer.

#21

• Getting to use the sword is a novelty, and often tricky.
• Shooting laser beams at your opponent is also fun.
• It's the second entry in a series that's still going strong to this day.
• One thing I loved about the game was the little cut scene vignettes you unlock when you complete the single player part of the game with each different character.

#19

• Back on the PS3 when PSN was just for smaller games, not full downloads of major releases, this was one of the biggest games on the service and also the best.

#18

• A reboot of sorts for an already well-established and successful series. The main reason I like it so much is the unique art style and the way the world comes to life the more you progress and cleanse it.

#17

• People gush over this series' gibberish lore to make up for the lack of actual story, but I say fuck the lore - it's all about the hellish combat really. This entry makes it more fluid than ever before. And prettier too, much prettier.

20.  Final Fantasy Tactics?
16.  Nier Automata?

No to both, though Nier: Automata is on my list, just not at 16. 16 is Horizon: Zero Dawn as Machina guessed.

Automata is the #19? Like, 2B or not 2B :P

#23: Hint 4: This is a spin-off series of a more popular and bigger franchise. The main villain of said franchise is forced to team up with the protagonist in the game in question to beat the villain who wants to destroy the world.

#21: Hint: You can choose one of several paths at one point in the game.