Kirby, I'll get out of the way, first.
vs
, its 55:45 or 60:40 in Mario's favor on default because even though Kirby can combo with his throws, air-auto cancel, gimp Mario(but not easily), has more ko options along with set-ups, has d-tile to out-space him if needed, and has anti-air moves, Mario has better frame data, kill him early, gimp Kirby due to slow air speed and can't snap the ledge so cape and fludd are useful for that, jiggle him since Kirby is floaty, and has up-smash as a anti-air move.
Customs: I would say its even because Kirby's upper cutter can not only snap the ledge and be difficult to gimp, but can combo out of his throws and use it Oos. Hammer bash, he can use it for a punish, but that's about it. Shock cape is good for another ko option and Gust cape is ok. Fast fireball to force approaches, combo or even camp.
vs
: Bad news for Mario. Its 45:55 in Meta Knight's favor. I think it was even before on the pre patch, but now on post patch, its in Meta Knight's favor, now. At least this MU is not as bad than in Brawl. I would switch to
or
if Meta Knight gives me trouble as Mario because at least they have a even and better MU against
than Mario.
Meta Knight is very difficult to edgeguard even with ledge trump, cape, and fludd, thanks to his superior recovery for him to avoid gimps and mix up options as well. While you have up-smash as a anti-air and can jiggle Meta Knight(not easily since his landings are good for mix-ups), Meta Knight can do it better with his up-airs and also has up-smash as a anti-air move. Meta Knight has the speed to approach and deal with Mario's fireballs because of their end lag; Plus, his disjoints can keep Mario out. Meta Knight can combo Mario and his n-air or up-b won't be able to save him from his up-airs to up-b, much so its best to mix up di to escape that deadly combo; Otherwise, he can even get a early kill off of you with his up-b. Its very important to mix up your recovery because Meta Knight can gimp Mario and if he reads it, then you're done. Both have good frame data and even ko options to battle each other, but while Meta Knight is light and Mario has better up-smashes(slighty, but forward smash), I think he has better kill throws with up-throw(off top of a platform) and back throw. Mario can also combo Meta Knight since he's alittle slow in the air to escape air combos.