Well, I can't really pin them down, so I'll give you my top picks and my reasons why. Bear in mind, I tend to view swords more pragmatically in terms of design, and that's just due to me being into real swordsmanship.
Gilded Sword:
Now, I love the sword's overall shape. I love the unique guard, and I especially love how narrow that point is, which is my favorite part about this sword. Good for thrusting and getting nice, deep, penetration. In terms of the profile taper, I feel the sword is pretty close to perfect.
If it had a distal taper too, it'd be the perfect blade.
And the handle and pommel aren't too bad, either, though I think it'd look better if the handle was just plain ol' dyed red leather.
But, I have two minor issues.
First, compared to real gilded swords in history, I feel it is a bit... simplistic in design. I'd much prefer if the gilding told a story like real gilded swords in history do, or had an artistic motif going on.
Take Emperor Maximilian's gilded longsword as an example.
The swordsmith for that sword clearly used the gold to tell a story from the hilt to the tip.
Plus, being a gilded sword, you could definitely get away with a gilded guard and pommel and still be in the realm of practical.
The other issue is while I like the overall shape of the guard, I feel it needs to flair outwards a bit more so if Link does bind an opponent's weapon (something you do even in sword & shield or sword & buckler), and it slides down, the guard will catch it better.
Overall, a well designed sword with a few minor tweaks I'd make. The raw sword itself is very much functional.
Ordon Sword:
I actually like the sword's overall design. It's a simple, straightforward design that's very much pragmatic.
That said, it's not perfect.
The sword appears to me to be an Oakeshott type XIa, and all swords of that type in Oakeshott's typology are allowed to have a fuller run from the guard all the way to near the tip. Thus, first design change I'd make is to make that fuller more prominent. This should make the sword not only look prettier (because a polished fuller gives the sword a nice luster, especially when oiled and polished), but also lighten the blade.
Swords don't need to be beefy, because they're cut-and-thrust focused weapons, thus, with a sharp and pointy sword, it doesn't take
much to cause horrendous wounds with a sharp sword.
Second, either that guard needs to be ground down some, or the quillons need to be a touch longer.
Third, the sword is clearly a one-handed arming sword in terms of blade length, blade typology, and general use, thus, I'd actually change the handle to reflect that, by making it shorter. They seemed to have put a handle for a two handed sword on a sword that's designed to be used in one hand, for... reasons.
And finally, like with many swords in Zelda, I feel they all could use some tapering to make them sharper and pointier, namely, this needs some distal taper, and for European style swords, many of them are lenticular in cross-section, which helps the sword hold a tougher edge. The sword seems to have a hexagonal cross-section, and that actually means it's not going to cut as deep, due to how the edges are ground.
A double edged arming sword with a lenticular cross section, sharpened and tapered can get sharp enough to shave hair, and it's a very tough edge, which is important for bind work when the swords are touching.
Final change I'd personally make, is a copper wire rap instead of red leather. Nothing against leather as it's a fine material, but wire wraps are far
far superior in my opinion. They make for my personal favorite handles as they give you a
really secure grip. Both wire wraps and a katana's ray skin plus ito wrap make for my favorite handles because of how secure the grip is, you also know instantly, just by feeling, where the edges of the sword are, which helps in edge alignment, one of the fundamentals of cutting.
But, I see nothing wrong with the leather handle, that's just my personal preference.
Overall, there's not a whole lot wrong with it, that's just me taking a good foundation and improving upon it.
Lynel Sword:
Surprisingly, this is actually a quite functional design, as it has nothing in common with European or Asian swords, but, it shares everything in common with African konda style swords, which are pretty powerful cutters.
That said, the only change is proportions. Either the blade is ridiculously large, or that handle's really tiny.
The chain knuckle guard is actually pretty historical, as early Polish style sabers had chained knuckle guards before, so I see nothing wrong with this other than proportions.
Eightfold Longblade:
Everything about this sword is perfect.
The blade? Perfect for an odachi. Differentially hardened and has the right tapering.
The guard? A straightforward, yet artistically designed tsuba, which you'd expect for a Japanese style sword.
The handle? Again, perfect. It's ovate, and contains ito wrapping, which I said earlier is second to wire wrapping for my preferred handles, ensuring a nice, secure grip. Plus, it's the right length for an odachi.
10/10, flawless in terms of design and practicality.
Fierce Deity's Sword:
Oddly enough, such a sword is actually functional.
There is actually a design philosophy that the sword has, which, according to Ilya from That Works and Man at Arms, he said it's constructed like a multi-core Viking sword, but missing the inner core, which ties into the Buddhist and Zen philosophy that the whole world is supported by nothingness.
And considering Fierce Deity Link himself shares so many similarities with actual Fierce Deities from Japanese Buddhism, the sword's design makes sense.
In general use, it seems to be a greatsword optimized for cutting, which is fine, but I feel that handle needs to be a bit longer, and it seems to be too small for the blade.
Surprisingly, I feel it doesn't need a guard, because what's a little hand damage to a god?
So a simple fix in the handle is all this needs, the sword's foundational design is very much functional and optimized for cutting, which is just fine in my book.
