After having replayed Persona 5 Strikers, I can say that this game simply exaggerates everything that Persona 5 did badly whilst also missing a lot of what it did well and falling prey to being a needless sequel to a completed story.
It's safe to say that this game is quite literally just a thematic rehash of the original game as it desperately tries to copy what made the original as successful as it was to poor effect. Everything down to the story structure is the same with the only real difference being that it tacks on darker backstories to the Jail Monarchs in an attempt to either redeem them or make them sympathetic which almost never work. Instead they're hamfisted sob stories without any tact, nuance or integrity to make any of them anything more than frustrating or cringe worthy which is especially true in the earlier parts of the game. It felt like a Persona checklist more than a sequel to Persona 5 as it simply just added things that it felt it needed to have.
The game doesn't offer much for the returning characters either who have their character arcs retconned only to receive next to nothing in return. Pretty much everyone in the game is much blander than their counterparts in both the original game and Royal, even somehow characters like Ann who literally just embodied tropes in the original game, who mostly weren't very nuanced or interesting characters in the first place. Even Lavenza somehow manages to have less actual personality than her original game counterpart which is incredibly impressive. Of the new characters, I can safely say that only Akira, Akane and Zenkichi had anything actually worth mentioning. Sophia is just an Aegis clone but with the waifu pandering meter toned up to 100 with all of the other Jail Monarchs being nothing more than clones of the original Palace Rulers except more exaggerated and having even less intensity.
Gameplay is a mixed bag. It does away with Persona's signature calendar system, which is actually a breath of fresh air, but at the same time the dungeon design and game balancing takes a huge hit. The lack of social links makes the fusion system a lot less rewarding and the action gameplay has a lot of QOL missing namely surrounding the checkpoints. The dungeons were actually quite boring as they did away with the distorted and unique landscapes for standard Japanese cityscapes with thematic changes. The gameplay, as expected of a musou, was very button mashy but also attempted to include Persona 5's already
half baked stealth elements which were hit and miss to if they even worked due to bad prompt placements and a lack of actual stealth spots. Combat had quite a bit of SP problems especially in the beginning. Namely because it encourages you to hit weaknesses like the original game but with far, far more enemies in dungeons. There are ways to mitigate this however those simply drag the game on.
Simply put, Persona 5 Strikers feels much less like a sequel and more like a retelling of the original game as it hardly tries to do something different or have some form of identity with it's writing. It is, as a certain reviewer would say, quite literally Persona 5 without the heart. It's a clear cash grab that could've been much better had they actually put more effort into writing it.