I own both a MW longsword and a MW katana
MW longsword @ 1.8 weight MW Katana @ 1.3 weight
100 speed 103 speed
39 cut 38 cut
25 pierce 17 pierce
106 length 95 length
333 repair 464 repair cost
I mean compared side by side its obvious which one is better, longsword hands down, katana has a speed advantage but not really once you count weight and the stun effect of heavy weapons into it (katana gets stunned by about every weapon after the weight nerf)
and similar weapons in the repair cost of the katana kick its ass or you have guys nearly same speed omniblock 1h weapons like mw espadas and italian swords or even war hammers (which are all close enough in speed to a katana, combined with katana damage doesn't break shields)
katana's nerf was so major it left it being basically weaker than a bastard sword in alot of ways, the people who argue for its potency have never used one, in fact guys like Urlukur are pure 1h'ers forever
I'd add weight back into the katana, the fact now that people are just using MW war spears/red tassel spears/iron staffs etc at same kind of top tier speeds(97+) but with the polestun they're doing it like katanas never could as high agi spammers