Dashdancing and lasers are very good vs Peach, she's not good at dealing with them. If Peach is closer and grounded, don't be afraid to shield. After dash attack, Peach's approaches moving forward just get slower and take even more time. Try not to rely on fullhops to stay safe as much. unless you can also create horizontal space wavelanding on a platform. If you have the time to fullhop out of the way, you probably have time to wavedash out of the way, and definitely have time to do the more basic escape options (whether or not you can punish after those is a different story).
You're doing a lot of earlier nairs, which I understand may be in an attempt to beat out some approach by Peach, but these are ridiculously unsafe from the ranges you're doing them should Peach decide to block, and even more unsafe vs. CC. It's also probably not going to beat dash attack.
The jabs are also working, just beware of CC. If Peach CC's the jab, you're pretty much screwed.
From the ledge, when Peach is floating like that, you shouldn't drill, even if she's going all the way forward. Get right at the ledge onstage as quickly as possible, and shield or roll if she approaches (shield with di forward is safer). Otherwise, attack from that position rather than with a double jump from the ledge.
Don't do moves that knock Peach down when she's in the air, keep her up.
Try to stay close enough to Peach that you can always punish turnip pulls if you aren't lasering.
Bair to keep Peach off of you. You could also utilt more.
Just take your waveshines when you get them, try to finish with grab usmash, dsmash (at the ledge) or utilt at most percents. Stay on the ground more or go to platforms when she has a turnip. Beat the weaker ones with aerials. If she's approaching while she throws a turnip, you can use reflector at later percents/versus stronger turnips.
In general, you don't need to jump as much in the neutral, dash attack is by far Peach's fastest way to close ground between you.
If Peach has to recover from super low, but is close to right under the stage horizontally speaking, you can jump (or if you're on a platform, wavedash or drop) behind the parasol hitbox and snatch the ledge without conflict.
Do more retreating aerials if you're going to pressure her with them, or try to get behind her, though she's a bit better at dealing with people behind than a lot of other characters.