Kinda hard to explain sometimes how I play against certian characters. But I'll give it a try.
If Snake is camping you, I already explained how to out camp him and all that. So that you should know.
Now outside of that, You first need to have a mix of BOTH aggressive and defensive came. If you don't or not balanced at both, this will be harder than it should be. It is also inportant that you have good evasion cause when dealing with Snake himself and his set ups, you will need it. Learn how to evade well in general. Then apply that with Peach.
Next going in on Snake. You can use turnips of glide tossing or fair/bair. But space it. Just in case he wanna to side step or shield to tilts. Common **** right here. Some may roll behind you. This is why you space so you can get them and be safe.
Use lots of Jabs. Jabs get at snake well. They can stop his DACUS. Turnips can too. That is the only type of mobility he has. He is slow. With good ebasion makes it hard to hit you cause of this. So for that we would rely on pojectiles.
You can NOT, stay in side snake for too long. This is why I say you need to have an aggressive game and defensive one. And from my records and what I seen, about 96% of Peach players are aggressive and some most in that range don't have a defensive game, or not a very good one. And this is a problem I see in her meta game. always wanting to attack. And I been saying this for a while. It will bite you in the azz. Peach is not an aggressive character. She can be played that way but comes with a dangerous price and it reduces your options to kill better since she has killing trouble to begin with.
When you get in snake, pound his with good pressure and spacing. Get your damage on (aggressive)
When he is out of your assult of range, GTFO and run, retreat, etc. Then use turnips of spacing tatics to get some small damage on him to refresh your moves and give him a hard time. You the "out camping strat" On snake as well to screw him over and get him damage. Same time move in slowly. You can create openings this way but be quick about it and smart. (defensive)
Grab him alot and this is not to hard with jabs. Jab once to grabs. Get that damage. and if he is under 100%, throw his azz up. Always keep him in the air. With turinps up there and then you wanting below to strike, it can be really hard for Snake to recover. Don't be so quick to toss his azz off stage, you are really not gonna go anywhere with that.
Also if you know snake will launch tilts, just move in and out with spaced Bairs, and hit him. His tilts don't have quick coll down time, so he will be open for a hit. Limit your loating cause snake is already slow, and floating will make you show and match won't really go anywhere. Short hop your dairs.
And have a ground game. Most Peach players love to float to Dairs alot. Snake can shut that down. Then you have to fight him on the ground. And some Players have poor to no ground game. This is another problem in her metagame.
I know there is more but this is all I can think of for right now. And I find snake easier than meta. But fighting them feels the same. Meta is fun to fight as Peach and snake just makes me laugh.