Call me basic, but MK is my favourite Kirby character. I guess the cool, lone swordsman trope just does it for me lmao. And let's face it, his voice, in whatever media he shows up in is always... very good, whether it be the anime or Smash Bros, regardless of whether it's subbed or dubbed.
Yes, I think the blue orb with limbs is a handsome boi, deal with it.

I do like that MK (in the games) has his established little crew of fellas (aka, the Meta-Knights + the rest of the Halberd crew). I love characters that treat their minions/underlings/whatever well/as friends/family and have their undying loyalty. Special shoutout to Sailor Dee, the goodest boi.

I also find it funny that anime MK is canonically bigger than game MK (In games (pre-KatFL): Kirby and MK are the same height. In anime: MK is bigger than Kirby. Kirby both in the anime and games is of his canonical height, 20cm, making game MK smaller than anime MK.

I actually have a theory about anime-verse Meta Knight, so strap in.
In episode 3 it's revealed that the first star warrior was created by Nightmare. Fumu/Tiff just kinda assumes it's Kirby, although that wouldn't really make sense?
We aren't really given a timeline or anything about the GSA vs Nightmare war, but if we assume it started around 10 000 years ago, aka when Nightmare started conquering the universe (if I'm remembering the details correctly), it would make absolutely 0 sense for the first Star Warrior to be Kirby, he should be an adult at that point.
The first Star Warrior was also depicted holding a sword when defying Nightmare. Kirby can barely hold a sword in episode 3.
He also doesn't usually jump into action unless his or his friend's lives are threatened, or he's told to fight the monster of the week, making him not really that defiant?
So if it isn't Kirby, then who is it?
Since I'm rambling about it in my MK shrine you can probably guess who I'm leaning towards.

I just feel it would make sense. Kirby may not have been the first, but we can assume it was someone of his species, due to the spherical shape of the 'silhouette'. While it isn't ever mentioned Kirby and MK are of the same species in the anime... literally why would they not be.

Back to the sword; even before he got Galaxia, MK has always been seen using a sword, and is shown to be very skilled with the blade in general. Maybe he was created with the intention of wielding a blade.

Next, Kabu straight up says he learned all of the info on the first Star Warrior from Meta Knight... how would MK know all that if he wasn't the first? One can argue that maybe the first was someone else who told him about it, or that he heard it from another Star Warrior, but I imagine whoever it was wouldn't exactly want to go around telling people they are a creation of the enemy, for... obvious reasons.

MK is never shown or been told to have wings in the anime adaptation. Most people I've seen do like to think he still has his wings, but is just hiding them, since they might make him look like a demon.
I wholeheartedly support this theory (it would also explain how keeps getting to high places to stand on, and somehow always manages to show up everywhere at a convinient time).
Assuming he has wings in the anime, and is a creation of Nightmare, it would explain the 'demonic' look of his wings. They make him look like a demon because he was supposed to be one.
Meta Knight also clearly knows a lot about... a lot of stuff, so it's safe to assume he's quite old.

A random thing I've also noticed is that both MK and Nightmare have a dark blue cape that they wrap around themselves.

Anyway, this is was really disjointed because I'm not good with words. I kinda felt like I was writing a conspiracy theory lmao.

Headcanons

Just some random headcanons of mine. I'll be separating them to Animeverse!MK HCs and Gameverse!MK HCs.
Some are more based in canon, some less so. These are just for fun and my own self-indulgence more than anything.

Gameverse Headcanons

• Protected Dreamland with Dedede before Kirby arrived
• Bisexual + Biromantic
• He/him, they/them pronouns
• The Halberd-crew is like a family to him
• Speaking of family, he's married to Dedede
• Has no interest in having biological kids, but doesn't mind adopted ones
• Has PTSD from the events of Planet Robobot
• He also very much doesn't like Susie and has a fear for anything related to doctors or medical equipment
• Has some scars, the most notable being left from being turned into Mecha Knight/Mecha Knight+
• Only the Halberd-crew, Dedede and Dark MK know the full extent of how bad the incident with Susie was for him
• Workaholic + Atrocious at taking care of himself
• Purrs + general cat mannerisms
• Gets very flustered if he receives romantic verbal or physical affection in public
• Still gets pretty easily flustered by affection in private, but it's much less likely to just make him shut down on the spot

Animeverse Headcanons

• Like I stated in my thery, I do HC that he's the first Star Warrior/created by Nightmare
• Has wings but they're hidden by his cape
• Bisexual + Demi-Biromantic
• He/him pronouns
• Depending on how I feel, he may or may not have been in a poly relationship with Garlude and Jecra (Knuckle Joe's dad)
• May or may not be Kirby's dad, again depending on how I feel
• Like Gameverse!MK, Workaholic + Atrocious at taking care of himself
• Purrs + general cat mannerisms, although he hides them more than Gameverse!MK
• Has frequent nightmares + PTSD
• Has quite a few scars, although he keep them pretty well hidden
• He definitely has a scar left from when he ended up with a kunai stuck in his foot when Yamikage betrayed the GSA
• Even worse with affection than Gameverse!MK

Credits
MK corner graphic: By Nintendo, ripped by Drshnaps on spriters-resource
The screenshot is from Hoshi no Kaabii/Kirby Right Back at ya (anime) (the one with subtitles is from Misty Sparkles' Kirby breakdown video)
Bottom corner graphic by Hal Laboratories
Forgotten Land render by Hal Laboratories
Background image by HAL Laboratories, ripped by nateismyname on spriters-resource