I LOVE the yoshi matchup. I played Flo Yo this weekend in pools and barely lost. In chicago, I am the yoshi slayer.One of my closest friends and dubs partner used to play with me every day, he was a yoshi main and we even did double yoshi in teams. I absolutely love this MU. I am even undefeated in the yoshi ditto in tournament.... I love yoshi
I personally think we beat yoshi. You can disrupt his spacing very easily with quick attacks and offensive fair/RAR Uair if the yoshi is aggressive. If they yoshi is at all aggressive, do NOT just sit in shield. That is what yoshi wants you to do. His fair is safe on shield and his egg lay easily lets him get through your shield option.
You should try to react to his aerial movement and powershield fair if you want to be safe. Fair is the only aerial that really threatens us. Fair is only effective at a set distance too. At this distance NONE of yoshi's other aerials will hit pikachu, so you basically have the ability to cover every option by just reacting. Pikachu is very hard to keep at that set distance (Unless you are hiding in shield). I usually just try to predict jumps and fair... This matchup is literally just spacing mixups
Against defensive yoshi, we just have to play the reactive poweshield game.
Also, Don't be afraid to shield if you do not want to die. Yoshi cannot kill us since he normally nets kills off bad landings and edgeguards, so he has to kill us with raw kill moves. Against flo yo, I think that I usually lived till like 200% when I did not SD or do something dumb offstage "Please just die already" LOL. If he grabs you, he can't convert that into anything, so don't be afraid to shield a lot, just be aware of why you are shielding. If the yoshi starts egg laying or grabbing you, just let them keep grabbing you, this will condition them to keep covering that option if you refuse to stop, then you punish the egg lay by just usmashing it. Cover dash grab with any evasive defensive option (mix it up), then punish the HUGE cooldown on his grab with an usmash or Fsmash (HSB if customs, I guess)
also flo yo told me that more pikachu players need to start edge guarding us and figuring out the percents that each of our moves will be able to break his super armor at. (I have personally killed a yoshi with jab to break his super armor because it stopped him from sweetspotting the ledge)... But yeah we should lab that and figure it out
I do have a LOT more experience vs aggressive yoshi mains as apposed to defensive yoshis, so keep that in mind.
If anyone wants to add advice on defensive yoshi mains OR correct me on what I just said, that would be pretty cool lol