Just put it at 55-45 or 60-40 Peach I don't know which it is you guys probably know better than I do
Peach is gay, Sonic is...well Sonic is awesome but still annoying to fight against. Getting past Peach's Floating crap will suck if she refuses to approach you and pulls off lagless rubbish on your sheild and pokes and jabs and stuff. Use Bair as Sonic but just be careful since Peach can hit you with her Fair if you miss or just chase you on the floor. Just punish her with Bair and stuff. Recover as best you can, Sonic's recovery is pretty screwy vs Peach anyway, you can die early if you're not careful
DI diagonally upwards against her stuff, she kills horizontally with Fair and the like. Chis is stupid and lives to about 190% if we're both playing well and even if he does mess up a bit he normally survives to around 160%, something stupid like that. Getting a hit on either side is really hard since their range his pretty even and I've found landing a kill move on Sonic is ridiculous since he moves so bloody fast but when coming down with my Fair on his sheild, provided I pull away a bit before and after the Fair comes out Sonic can't grab Peach but then Sonic can just roll away and run away and no one takes any damage and ARRGGGGGHHHHH
Turnips are silly, catch them if she's intent on spamming them, they're not fantastic vs Sonic anyway. I mean, they're Turnips so they're still really good but they lose their effectiveness when Sonic can run up and grab you, probably even if Peach does Turnip slide. If she has got a Turnip out watch her attack pattern and smack her or just wait until it's gone. Glide tossing can be used to punish Sonic's Bairs so be wary of that
If your Peach is silly or a risk taker, get ready to angle an F Smash up when she's recovering and coming towards you with a Fair, it'll probably smack her in the face before the Fair hits you. I've died a few times in the past to this and got a few Peach's doing this as well. Also, if your Peach mispaces her Fair or Jabs, grab her. Grab her when the Fair hits your sheild before she jabs and if she does jab, spotdodge if she goes for a 2nd one or grab her inbetween, judge the distance first so you don't get slapped. Don't go running towards her like a crazy fool cause her D Smash will slip you up. And don't try hit her out of a Fair if she SH Fair's by jumping off the ledge, shes invincible and you'll get hit
Neither side can kill very easily at all when playing carefully meaning this match will go on forever. Space for all your worth and if Peach is doing the same...well, you'll be there for a long time