Olimar : 30-70 vs Peach. I'm not joking. I think this is pretty generous too. This is a horrible, horrible matchup for Olimar. I regularly 3 stock Olimar's if that have never played me. Let me explain.
A) Peach's back air will outprioritize anything Olimar has, and she can jab before his grab comes out from any of her landing aerials. Thus, it is impossible for Olimar to ever grab a smart Peach.
B) Down air will beat out all besides purple pikmin, and outprioritizes Olimar's forward and up airs, and upsmash.
C) Peach bomber will bounce off pikmin, making her free to spam it for approach while Olimar throws Pikmin.
D) Turnips **** his recovery. One turnip and you can edgehog him.
E) Forward air will also outpriotize his upsmash AND still hit him through it.
F) Olimar can't grab peach. Jab comes out too fast when she lands. If he doesn't grab, she can grab him upon landing.
G) One downsmash will kill all the pikmin on her.
There just isn't much Olimar has going for him besides purple pikmin and using his UP B to mess up her float approaches. But if Peach adjusts to it she can land and then get in a free forward smash. Even if she doesn't adjust to it, its just a small hit, low percentage, and doesn't do much. Not to mention he needs to be holding all his pikmin for it to have much reach, pikmin bettere served throwing at her.
If Olimar DOES hit her, he can kill her at decent percentages though. That's the only reason I made it 30-70. But the Olimar has to be pretty **** tricky to land any of his smashes on her.