The short answer is yes you can dive in; but if you have time, playing the first two would be ideal
If you asked a member of the Platinum marketing team, they’d probably tell you that Bayonetta 3 as a standalone story that you can dive into. But if you asked Platinum dev and executive Hideki Kamiya, he’d urge you to play the initial two games first. The latter is mostly true: if you can play the first two, you’ll get a lot out of it. If you play Bayonetta 3 first you’ll mostly be fine, but there are bits and pieces from the original two games that will greatly benefit your enjoyment of the story, and certain character interactions.
Minor vague spoilers below in terms of themes, but nothing specific
In Bayonetta 3, the titular protagonist and her team are squaring off against a new threat: humanity. Or rather, humanity evolved, by way of “Homonculi.” Bayonetta has essentially conquered hell and heaven in her original games (which are present throughout mostly in the form of challenge rooms), but this story is new, and most of it will be easy to glean/pick up as said threat is introduced. Viola, the new playable character, is also a clever way to usher in brand new players and ground them to this third entry.
The action speaks for itself. Bayonetta 3 has myriad tutorials, as well an easier mode, and even an accessory that can do auto-combos (you just need to purchase it from the shop). By all counts, it’s arguably the most accessible entry in the series from a mechanical standpoint. You can get the gist of what’s happening through a lot of early exposition, ride out the adventure with Bayonetta’s new adversary, and pick up the game while you’re at it.
That said, where you’re really going to get a lot out of playing the first two games is the emotional resonance of the final act, and the character interactions. A few people kind of just pop up, and especially toward the end of the game, you’re meant to react to them on a more personal level, and vibe with the narrative twists.
If you have the time, you’ll likely get a lot more out of the last portion of the game, specifically the ending. But if you just want to play a game with a good action foundation and come along for the ride, you can totally do that too: especially if you have no intention of revisiting the other two games.
