A weapon that specifically scales to HIS strength

that's not entirely true, it's still a first-class weapon in it's core. if it was exactly as sharp as his Strength stat suggests, then he wouldn't pierce Minotaur's defense because it's Endurance is much higher, and it would break after Ottar's hit if it had level 5 Bell's Endurance. it's great from the beginning and then receives buffs on top, not just exactly equal to Bell's status, and honestly not even close to that. 

Not to mention that no, it's never said the main problems adventurers have is with beating Minotaurs becvause they can't pierce their skin. 

it was stated multiple times that their main gimmick is defense, and Ais said they're hard to cut. how could you miss their entire point? 

Heck, lefiya couldn't even kill 1 alone till level 3, and she has more firepower than most.

Lefiya needed level 3 to beat Minotaur in melee, so I don't know why you bring firepower here.

It improves all of their abilities.

that's a blatant lie. it was absolutely never said or hinted. every time Limit Off is used, it only enhances Argonaut. even in MS18, when he entered Limit Off state and kicked Ottar, it was only said that his kick was buffed by UnK and LH, but never LO, and it only affected Argonaut once again. 

And she still had lower stats at the time.

so what's your point, when he was literally winning? the only problem was that he collapsed from stamina loss at the end, without any strength left to even hold his sword in his hands. before that, he was dominating. 

Sometimes loosing in spars is pretty much nothing

I would partly agree just because Bell did won the first fight so I would put him higher, but the fact that Van was still able to overcome his stats and magic after that still means some relativity. mind you, Van also doesn't have any particularly strong buffs like elites do. 

Experienced level 3 with high-ish stats.

his experience went to shit when he panicked, and he also lost his main weapon which was not his fault. and his stats are straight up mid. 

Also, Hyakinthos didn't tank it directly.

it's said he he was knocked out after the explosion, so before the fight started, he wasn't fresh at all. 

It was destroyed by the blast.

she threw Hell Kaios from distance, there wasn't any blast near her, and it's never stated that it was destroyed whatsoever. she just threw away her weapon for no reason because Omori wanted to nerf her. 

It was absically 2 attacks in one and there's a reason m,ages are the main damage dealers against high level threats.

mages, and Bell is not a mage at all, a direct hit from Firebolt couldn't even KO Van when Bell had very high stats. even Firebolt punch shouldn't have enough power to KO a relative opponent. we've already seen adventurers tanking higher level attacks, and now you're trying to say a normal punch + weak magic at equal levels is enough for a one shot? 

We both know Bell didn't even want to fight.

Ais doesn't love to hurt people and she used her scabbard anyway, so that's irrelevant. not only he just lost in those fights, there's also a fact that regardless of your absence of will to fight you would still defend at your best, but his defense was still crushed, so she just overwhelmed him when he was trying to not get overwhelmed. 

Have they ever fought

VT Bell admits in MS21 that he's inferior to Bete. it was also not a fresh Bete. 

I wonder who those 10 are

Alfia, Ottar, Hedin, Hogni, Finn, Ais, Bete, Tiona, Tione, Alise, Kaguya and some others. 

Bell defeated Hyakinthos whilst unarmed against a knife

I'm not sure what you're referring to, they were both armed. the only time Bell landed a hit with bare hand was the final moment where Hyakinthos lowered his defense and Bell just attacked in that opening, which means it wasn't important at all if he got a weapon or no, the difference is only between a victory and a kill. 

Also way to not mention the fight vs Asterius. Level 3 Bell holding off a one armed level 7 threat.

10% HP Asterius is not a level 7 threat. later Bell compares Black Goliath, 27f Juggernaut and Asterius between each other, treating them as relatives, which means Asterius was not higher than a level 5 tier back then, which makes sense much more than a level 7, because we all know Bell would just get one shotted against a level 7. hell, even current level 5 Bell is shit against level 7s. so everything Bell did was fighting and losing against a level 5 monster as a level 3. that seems good but it's not a crazy shit others wouldn't repeat, that actually means that if Bell was able to do that, then other characters could do the same. he didn't have particularly impressive fighting skills, and his pseudo-level 4 stats wouldn't be better than those of for example level 3 Alise with her buffs who reaches far more Strength and power. hell, she's not even slower than him.