List Explained

Acheron: 5 - Despite the last thread being made over a year ago, I still think Acheron is so good that it can't even be compared to other weapons; it's still just outright broken. Reasons for a five should be pretty obvious.

Barbarous Thorn Blade: 5 - As one of the main piercing swords it lives up to its name well; its fast attacks make it potent even to Undead and Gremlins, and its AoE charge attack gives it very effective crowd control as well as solid damage to big enemies that take a full hit from it (/Rabid/ Snarbolax, Vanaduke, Maulos, etc.) For this reason I strongly believe it is worth the five rating-wise, as it does what it's supposed to do to the best anyone could ask for.

Cold Iron Vanquisher: 1 - It's really hard to give this a description that someone can even take seriously. Why even bother. Just make Leviathan Blade and forget this [redacted] even exists.

Combuster: 5 - As a Brandish it gets a lot of hype and it lives up to it perfectly; the charge attack gives amazing crowd control and crowd clear and that alone makes it do well against any enemy type, even Gremlins and Beasts. Not much more needs to be said here.

Divine Avenger: 4 - In comparison to Brandishes it is a more defensive weapon when compared to a Brandish's offensive playstyle, making it suitable in a different niche than Brandishes; it still has amazing damage output and its charge is absolutely spectacular, but it falls short in some crucial areas-- the fact that walls make the charge useless and that the charge takes a second to actually go off since the phantasmal swords float in mid-air for a brief moment before firing, make it unsafe to use in some situations, and by comparison its regular combo is a direct downgrade to Warmaster Rocket Hammer.

Dread Venom Striker: 2 - Weak hits, weak output; the Poison allows it to be a niche weapon if someone doesn't want to carry around a different Poison weapon and doesn't have Maskeraith, but that's about as far as its usefulness extends. Considering how useful Poison can be in end-game situations like Shadow Lairs, its enough of a niche to bring it up to a two rating instead of a one.
Fang of Vog: 2 - It has to be considered that Fang of Vog can inflict Fire on regular attacks while Combuster can't; its huge damage on its charge attack effectively makes it the strongest sword in technicality, but it lacks solid DPS and the charge has a very high tendency to self-Fire the user, making it a risk:reward attack where the risk is always higher than the reward. Even with maximum Fire resistance being burned by Fang of Vog causes significant damage to the user, making it inconsistent and lacking a usable regular combo without good ASI bonuses.

Fearless Rigadoon: 2 - Literally only giving this a two because Stun is overpowered. It rarely procs, the damage output is actually disgustingly low in comparison to Barbarous Thorn Blade and Final Flourish, and its charge isn't that great, but Stun is Stun.
Final Flourish: 4 - The same pros as Barbarous Thorn Blade but lacks the AoE charge. Don't get me wrong, the charge is strong, but it is inaccurate, unsafe, and just generally not a selling point for the weapon, while Barbarous Thorn Blade can use its charge to full effectiveness.

Furious Flamberge: 1 - Same disadvantages as Fearless Rigadoon except without the part where it has a good status. The weapon is honestly just horrible by comparison to almost any other 5* or 4* sword.

Glacius: 4 - The Freeze status gives it amazing crowd control, but it lacks a strong crowd clear that its two siblings Combuster and Voltedge have; by comparison, Voltedge has similar crowd control abilities while still retaining absolute dominance in terms of damage output, while Combuster has crowd control in the way of pushing all enemies to a certain position rather than freezing them in place, giving it better crowd control than Glacius with higher CTR. As a Brandish, it's still destructive in its usability, but the Freeze on its charges just don't compare in usefulness to Voltedge or Combuster.

Gran Faust: 5 - The amazingly-strong combo and defensive abilities of this sword just make it absolutely amazing, and the fact that it has a chance to Curse on the second hit is just icing on the cake. Its damage output is great, and although it lacks a usable charge attack, it more than makes up for that with its regular combo being so good. Although it may seem weird to give Divine Avenger a 4 yet give Gran Faust a 5, it has to be remembered that Divine Avenger has to compete with Warmaster Rocket Hammer while Gran Faust doesn't have another "heavy" Shadow weapon to contrast against.

Leviathan Blade: 3 - I don't think this one needs an explanation. It is the epitome of "The item can hold its own, but is generally outshone by others."

Obsidian Edge: 4 - Honestly I think this weapon should be rated lower than I'm giving it, especially when Acheron exists, but it's still a Brandish and by comparison it has the exact same pros as Combuster except it has a more useful status and is Shadow instead of Elemental, so a four is well-deserved.

Sudaruska: 3 - Generally strong all-around, with an amazingly strong charge that can be used both defensively and offensively due to its status. Its slow speed heavily gimps it in comparison to a Sealed Sword upgrade line. There's not much more to say here.

Triglav: 3 - Literally just copypaste the description for Sudaruska here, they're both the same honestly, just useful in different situations.

Voltedge: 5 - In the same boat as Combuster except Shock damage instead of Fire; it is amazing in places where enemies spawn in large waves or in a party with a Vortex user (Electron Vortex has beautiful synergy). Honestly, in comparison to Combuster, both can be interchanged depending on the area. Combuster may be better in a lot of situations, but Voltedge still has the advantage of absolute raw damage output in areas with grouped mobs.

Warmaster Rocket Hammer: 5 - The basic combo of this weapon is just absolute devastation. It's basically the elemental version of Gran Faust (wow bet you'd think it would be Divine Avenger), having a destructive regular combo and an almost unusable charge; although the charge of Warmaster Rocket Hammer definitely isn't unusable, in 100% of cases the regular combo would probably out-damage it; not unusable, just inefficient.

Wild Hunting Blade: 1 - Like Dread Venom Striker except slightly slower, giving it even worse damage output; the loss of Poison in exchange for a Beast bonus is just silly, and the phantasmal Wolvers hit their target significantly less often than the phantasmal sword from every other upgrade. Honestly, the 4* Hunting Blade is better than Wild Hunting Blade due to its faster attack speed and the fact that it has the more-accurate phantasmal sword than the Wild Hunting Blade's phantasmal Wolver, while still retaining the Beast: High bonus.
On that note, I'd realistically give Hunting Blade a two in rating, compared to Wild Hunting Blade's one.

Faust (4*): 5 - Gran Faust except its charge attack is actually usable. The damage loss is actually completely irrelevant when level 10 4* items are so close to level 10 5* items already (like 30 damage difference or something).

Winmillion: 2 - As a Gunblade, it has its niche uses to a certain extent; being able to actually effectively replace a gun in usage (this is a stretch, but it really can to some extent). While its damage isn't that great, probably due to the fact it is a 4* weapon, it does have its uses as a secondary weapon that you can use to manipulate a few things; the projectile from it generally causes things like Wolvers and Fiends to dodge, allowing you to take control of a group, and it actually has quite a bit of range on it allowing you to hit switches without having to carry around a gun. The fact that it's a sword gives it a close-range knockback option that many guns lack with the exception of Valiance, and it can be shield cancelled for a faster attacking speed. It's definitely not something to use as a main weapon, considering its abhorrent damage output and effectively useless charge because of its element of randomness, but it can be useful as a niche weapon.