Alright so I want all of you to ignore what I've said thus far because I'm approaching match-ups from a different perspective.
That being said I'm only going to comment on the ones I think I know from tourney (and non-tourney) experience.
Also note that when I say "bad" I don't necessarily mean terrible. In fact a lot of the time I mean that I'd rather go Snake (which is just a personal thing and probably doesn't apply to like 98% of you).
Also note that I'm not claiming that I am, in any way, a definitive or even remotely accurate source of match-up information.
-- bad (possibly one of Kirby's worst)
-- evenish (maybe slightly in DK's favor)
-- 70/60 Kirby's favor
-- bad for Kirby (ughu)
-- evenish (maybe slightly in Kirby's favor)
-- bad for Kirby
-- good for Kirby
-- evenish (probably slightly in Kirby's favor)
-- even (I've played this match-up a lot against various players and I think it's dead even)
-- lol wait wut
-- a little bad for Kirby (but Kirby can still do some stuff)
-- slightly in Kirby's favor
-- good for Kirby (some Snake players say it's his worst matchup, I don't know if I agree)
-- evenish (feels pretty even, might be a bit in Squirtle? could go either way)
-- slightly in Kirby's favor
-- slightly in Wario's favor
-- good for Kirby (guys the chaingrab in this match-up is just ridiculous; i need to test more but I did it today in tournament and the guy was DI'ing as hard as he could; ban Dreamland against Zelda because by the time fsmash will kill her dthrow to fsmash will stop working)
I hear that Ivy/Kirby is really good but I don't have experience in it. Olimar/Kirby is weird. I played today and I lost most of the time but I was having a hard time figuring out the match-up, plus the guy was a bit better than I am, so I don't know.