I seriously need some help dealing with her. Idk if I'm the only Cloud who struggles heavily with her but I just can't deal with her. Idk if I should rush down or play campy. It's frustrating. I know she's a new character and it takes a while to learn the matchup but it's just frustrating
You need to play campy and play patiently against Bayonetta. The matchup really deals with both ends trying to bait one another, but it's safer if you don't go after Bayonetta.
Cloud is the definition of an anti-camp character. If a character like Bayonetta camps Cloud, then she will allow him to charge his Limit Break, eventually getting buffed from its effects and having access to more powerful specials. If we talk about Final Destination, then Bayonetta's neutral B won't hit Cloud; the shots will end up slightly above him. Speaking of neutral B, if Bayonetta is doing it too much, don't be afraid to use Limit Break Blade Beam; the move has transcendent priority, making it effective against her.
Bayonetta has a lot of effective ways to start combos and has powerful attacks, but they all leave her vulnerable when shielded. This allows Cloud to get in a free smash attack, Cross Slash, or combo starter with d-tilt.
One thing that I learned with Cloud in this matchup is that you want to bait her a lot. You want to bait her into an air dodge (which, by the way, lasts very long) or get her to use Witch Time; this enables Cloud to get in a free punish. For example, if you d-tilt to u-air a lot, she might catch on to it and go for an air dodge or Witch Time; bait her into that and go for a different move.
If you are not patient and are very aggressive against her, Bayonetta will be using her smash attacks, combo starters, and Witch Time. Her smash attacks do a lot of damage and have a ton of knockback, side B will lead into combos in the air and can rack up to 50%, and Witch Time could have her get a free smash attack.
Off-stage is devastating for Cloud as well. She has ways to gimp him easily and her down smash meteor is practically a guaranteed KO on him.
tl;dr Play patiently against Bayonetta and go for some baits. If you go aggressively, you will get massively punished for it.
I will say that, in general, it's best to play Cloud patiently and defensively rather than playing aggressively and offensively.