Probably Krystal's recovery. And here I thought Lloyd and Little Mac couldn't be topped.

i hope you're talking about her recovery back in her reveal.
she got a new sideb that pretty much buffed her recovery game.
it goes at a longer distance AND didn't put her into freefall.

Well it did say move not moves, so yeah the up-b on it's own sucks.

I'd say Chibi-robo's down-b, it consistently does not work

Remember when it could suck up Giga-Robo?

Chibi down-b

wording implies her entire recovery game

boi you need to improve your wording game =P

Tell TSON or Geno to give me a buff or something
Also it's a good move sometimes, but I personally find Sandbag's neutral-b to be uselss if items are off. It's too slow and all you get is a capsule that might or might not explode.

I don't think capsules are that bad. I'm just conditioned to not use it since half the people online don't have items completely off.

honestly probably Sandbag's neutral special. It doesn't really work and barely works for gimping. I have yet to see any Sandbag players using it while playing seriously.

Chibi-Robo's down-b.
Straight up doesn't work, and on top of the fact that it's situational as well.

It does have invincibility frames even without grabbing something at least, so you can use it to like, idk... 3 frame "airdodge" out of tumble, but yeah still extremely situational
I believe the reason it doesn't work is because the invincibility frames end before the projectile hitbox disappears, i think literally all it needs is either extend the invincibility frames or speed up the animation
Also, if you pick up and fast fall near the end of the animation, almost every projectile can be pocketed without receiving damage, and if you manage to at least grab 1 projectile without "destroying" it from self harm, every other projectile will work as "intended" for the rest of the match when picked up, even if it damages you

my turn:
taunt attacks
nah, i'm actually unsure but i somewhat agree on Sandbag Neutral-B, by the time you spawn a capsule, throw it and hopefully have it explode on the opponent, you may aswell have SideB DAir spiked them
Hmmm... what about 's Falcon Kick as an attack rather than a recovery tool?

There are some specials that are really specific and hard to use, but the worst one by far seems to be Bomberman's side B, if you don't want do move your bombs this move is totally useless.
But if we talk about the smashes, I believe the worst one is Black Mage's down smash.