I have been PvPing all the time, since level 15. There is a lot to PvP right now, and there are more good PvP weapons than in DS2 imo. I have my own favourite tools for PvP, however I am very good in PvP so some weapons many of you here consider good, I consider a trash for PvP. If we talk about high level PvP with no-target fighting, using blind spots, parry baits, often parries than we have weapons that are no longer good:
- Dark Sword, Sunlight Sword, straight sword without thrusts. It is so EASY to parry it, parry bait it and poke them that I sigh every time I see another DS
- Farron GS- I will say only that Rapier, Estoc, spear, anything fast with range destroys Farron GS (and most heavy weapons). Even katana is good counter, you just have to either parry them or time attack while they are in animation recovery from first spin (window is tigh but once you get it- gg)
- Heavy swing weapons without range- easy to destroy
- Spear/halberd thrust spammers- easy to dodge and parry, very predictable
Now, If we talk about higher level PvP those are my top favourite weapons SO FAR:
- Rapier- it is always meta and will be, range, speed, stunlock, poke, parry baits, main-hand or off-hand. I have it in slot for Farron/Straight swords R1 spammers and heavy weapon users.
- Lothric straight sword- absolutely beast- unparryable Arts (like in all SS), thrust attacks with good range in R2 (and fast), fast R1 attacks like standard SS, rolling thrust and 110 critical damage shared with rapier and veeeeery few weapons in game. Two handed thrusts. Leo ring and Hornet ring works wonder for it and after parry it will do TON of dmg thanks to 110 CD.
- Carthus Shotel - absolutely great weapon for Shield Turtles and parry spammers. It deals damage through shields (like all Shotels) and its weapon art is unparryable (like with all curved swords except for dancer swords), making it great for parry spammers. You see guy that hide behind shield or try to parry you all the time. Take out shotel and keep hitting him with L2 + R2. It R2 in weapon art will make wide swing attack with gap closer- you can catch everything around you in 180 degree and you gap close to rolling back guy
- Astora greatsword- man....this baby....this baby.... Thrusts with R2 and then pancake with following R2. Wide swings to use blind spots, two-handed and one-handed thrust, HUGE range, fast chasing attack and BEST- Great Lance weapon art. Absolutely beast! Only minus- its art can be parried.
- Estoc, Sellsword twinblades, Old Wolft Greatsword/curved greatswords, great scythe are also great. Same is with long heavy strength weapons (especially Black Knight Great axe Art is great). Duel Maces are not bad, but easy to predict and poke with Rapier.
Uchigatana and washing pole are also not bad, I would put them in my personal tier 2-3. They are however easy to parry and their arts are parryble.
All my favorite weapons so far work great with Leo Ring (Lothric- thrusts, rapier- thrusts, Astora- thrusts), Flynn ring and hornet (Lothric and Rapier 110 crit dmg). And shotels thanks to their unparry arts and ignoring shield- are great in DS3.
I use quality build 40/40 (but plan to get more Dex for sharp rapier better dmg). Add to it if you can min-max 30 faith for Lightning Blade or Dark Moonblade buff and dmg skyrocket.
There is still STR weapons that I did not test but as far as DEX weapons and quality weapons go- those I mendtioned are imo best in higher lvl PvP.
All above is my opinion and experience