No Items. Metaknight ONLY. Final Destination.
Seriously, though Metaknight won't be banned nor should he. He's good, he might even be the best character in the game like some believe Fox was in Melee, but he is not unbeatable. In competitive play he will always be a difficult matchup(unless you are playing a scrub), but the better player will always win.
Characters are banned in video games because they possess broken moves, meaning the game was simply wasn't designed to handle it's usage in any way or form.
Every single one of MetaKnight's moves can be defended against, and or countered.
Even M2K, who many believe to have the best MetaKnight, could not 3 stock Azen's Ike, despite his tier position.
As cited over and over again Akuma from Super Turbo Street Fighter is a broken character, and is rightfully banned. In higher levels of play there are no 'tough match-ups",no bumps or neutrals or even lost rounds(similar to stocks in Smash),no other character can ever--ever win against him. His air fireball used in competitive play breaks the game , and he cannot be defeated unless you are a better Akuma.
MK has been known to lose to Snake as a possible counter pick, and I'm sure he's lost to several other characters in competitve play aswell.
If there is a player tactic or style that seems unbeatable, learn it, and counter it. I've found that Peach and Pit do well against his speed due to their sliding properties( Pit: Spot dodge | Peach Dtilt) and I've had my recovery gimped by a good Mario through the use of multiple airdodges->footstools as I retaliated ending in a caped Drill Rush.
I have never even seen a good Falcon 3 stocked either.(but then if we're playing to win we'll see him just as often as Mewtwo and pichu in tourneys for now anyway...)
In anycase, MetaKnight is not a broken character, just because you can't handle a player tactic, does not mean the game was not designed to handle a move, and he will not be banned.
On another note, Snake's utilt has the most unrealistic hitbox I have ever seen in a video game ever, but several characters have deceptive range(Lucario being the only understandable one) and the lag on it's ending allowing it to be countered would technically make it not broken. He's won't be going anywhere either.
To end this already too long post, if you're playing to win, you are using the character best suited to your style (if you play best using approaching or camping projectiles MK is not your guy). Don't let anyone tell you that the way you are playing or the reason you are playing (for money, for the challenge, ect) is not fun. You decide that.