Anybody got any advice for fighting this guy?
Learn the match-up really, really well. Meta Knight's options are limited, so you have a fair chance at guessing what he's going to do even though his mix-ups are very fast. If you make one mistake you can lose your stock so don't make any mistakes.
Use U-tilt to start combos at lower percents. U-tilt works great if Meta Knight tries to get behind you with either a Roll or with cross-up attacks (such as a Dash Attack that goes past you). Grab is a good option when Meta Knight is in front of you. Grab won't work if he baits it with a Dodge. In that case you can hold Jab and catch him as his side-step finishes (it's also sorta okay if he ends up holding Shield because you can mix up the Jab with Jab-1/Jab-2 or try to go for a shield poke with Vulcan Jab).
At mid to percents start using more D-tilt and the weak hit of U-tilt (the ending hitbox that sort of hits in front of Kirby). These can lead to better combos, set-ups, and pressure then stronger attacks. Grab is still a good option: damage is damage.
Aerial attacks are good in this match-up, but they're harder to land since Kirby telegraphs his attacks much more in the air. Not only is Kirby slow in the air but his aerial attacks have much more start-up required than his ground attacks. The advantage here is that if you can land aerial attacks they have much better rewards for the most part. D-air combos into all kinds of good things (mostly Tilts and Grabs). N-air can combo a little as well and has very quick landing delay, but it's range is a little short. U-air is hard to use as a lead, but does a great job setting up for other attacks at lower to mid percents. F-air is sort of hard to use but can be used for aerial spacing. B-air is your go-to for getting KOs since it can start KOing Meta Knight around 100% give or take depending on Rage and how far to the boundaries you are when you hit Meta Knight with it.
Believe it or not, Kirby's Special Attacks are fairly useful in this match-up. Inhale gives an option against a Meta Knight who is baiting with Shield, and getting Mach Tornado is pretty handy. You can use Mach Tornado to punish Dodges, for instance, or you can use it as an a back-up recovery option (having a horizontal recovery option is nice even if it's likely to get you punished). Final Cutter can be used to out-space Meta Knight's sword attacks, but you really have to be amazing at reading
and spacing to benefit from this. Final Cutter is also an amazing option to use if you can time the Meteor Smash right as Meta Knight rises up with a Shuttle Loop at the ledge. Spike City! You can use Stone in a similar way to catch a Meta Knight who uses Shuttle Loop to recover. Stone will completely beat out Shuttle Loop and will usually net you a KO. Be wary of using Stone against a Shuttle Loop up at the top of the stage. Yes, it KO's Meta Knight at really low percents, but it takes a long time to start the Stone up and thus your timing has to be impeccable. Hammer is actually a really good option to use as a punish against a whiffed Shuttle Loop, Tornado, or Drill Rush. Those moves have a long cool-down and lag time, so if you're watching closely and defend successfully you can get charged Hammer KOs for that extra disrespect.
The hardest part of this match-up is dealing with Meta Knight's speed and pressure tools. Technically speaking Kirby has something to deal with anything that Meta Knight throws at him, the problem is making sure you do the right thing at the right time.