Don’t use meta weapons unless they “feel natural” I use a pole hammer(some of you may have seen me Corrupt Divine), and I beat claymores and bandis (and a lot of other weapons) more than I lose. Sure I die to the claymore and the bandi if I make a mistake because they are hard to recover from. But generally I’ll win or come closer because I learned from my mistakes when I fight them again. I’ve gone 1-2 with people who main maa and are level 35+, they’re annoying to deal with at times but it is possible and some times you just need to switch weapons to something fast, I prefer the shortsword as a vanguard and norse as a knight.
The claymore is fast but doesn’t do terribly much damage compared to other vanguard weapons if you feel risky you can wind up and charge in during the release of your weapon, yea you take a hit but you get a bigger one in. This assumes you can use distance widely and know how to deal with face hug type attacks.
Maa are a bitch, but if you fight enough of them you will start to find habits that people have(I can usually figure them out in 5 or 6 fights) and you can exploit those. And in lieu of that if they have a shield since they can’t riposte with a shield beat on them and be agressive to force them to run out of stamina. If they have no shield try to play chicken a bit you might have to take a hit and be ready to respond to a face hug to learn what they do before they dodge in. But a lot of shieldless maa like to dodge stab, with footwork and the right manipulation of your swing you can drag your swing and avoid the stab and quite often wham their heads.
It really comes down to experience though and footwork you need more of it, there are always ways to improve footwork.
Just keep playing, some weapons are OP statistically but just ignore that meta stuff and find something that works best for your natural play style. You’ll always do better than you would have just taking the OP weapon bonus if they’re the same thing.
You suck play more, find a weapon that suits your style and get better.