Persona 5 Strikers is a spin-off title of the Persona series and the direct sequel to Persona 5... not Royal. Still, even if you've only played Persona 5 Royal, you won't need to play Persona 5 before jumping on Persona 5 Strikers, since Persona 5 Royal is just an enhanced version of Persona 5 and not a different game.
When I finished playing Persona 5 back in 2019, I remember wishing for a sequel, and it seems like my wish came true... in a way.
Despite being a sequel to Persona 5, Persona 5 Strikers shares a similar narrative structure. Overall, Persona 5 Strikers has merely a good story, just not an exceptional one, like Persona 5.
The gameplay is completely different though; while Persona 5 plays like a turn based JRPG, Persona 5 Strikers plays like a mix of turn based JRPG and hack 'n' slash, it's challenging, it's quite fun and it works well for the most part.
The characters are still awesome in this game, and the additional characters are actually great too.
It is no surprise that the music is fantastic, coming from a Persona game.
Also, the art style is very stylish and charming, it's not as impressive as in Persona 5 but the quality is noticeably better.
Unfortunately, although the gameplay itself is fine, the dungeons get a bit tiring after some time, unfortunately.

Pros:
+ Nice story
+ Fun gameplay
+ Engaging characters
+ Amazing music
+ Beautiful visuals

Cons:
- Tedious dungeons

Narrative: 7/10
Gameplay: 7/10
Content: 8/10
Characters: 9/10
Music: 9/10
Art Style: 9/10

Final Rating: 8/10
- Great -
For Persona 5 fans like me, Persona 5 Strikers is a love letter in a form of a spin-off videogame.
For the people who haven't played Persona 5 though, Persona 5 Strikers is still a good game.

Do I recommend it?:
It depends; fans of the series should give it a try while newcomers should play Persona 5/Royal first.