The ESRB since its inception has been erroneously leaking some information to us for the future of any title, this is what happened with Bayonetta 3 which indicates future DLC content, this appeared in an indirect way related to some in-game purchases.

Purchases in Bayonetta 3 included some cosmetic items for some of the characters, but it seemed like they would require real money, which now indicates a new addition to the game. These ideas are wrong and no in-game purchases were found.

If this is true, it means that the game's ESRB rating means that the DLC (add-on) has been in development for a long time, as this rating for the game was made a few months before the game was released, but don't take the leaks seriously, this doesn't directly confirm that the gameplay will be receiving DLC in the near future, but it's entirely possible that the developers of Bayonetta 3 have more content planned for the game.

Recently, PlatinumGames studio talked about its own vision for the new part of the series, which was semi-open, so any future DLC could add more adventure. Don't forget that the game is available for purchase exclusively on the Nintendo Switch platform.