Top used PvP weapon is katana type. Fishing pole for those who have no shame at all.
Dark sword is the only straight sword that is being used often. May be Astora from time to time, but I can't recall anyone with a broad or longsword, even though I had over 50 tongues, and a dozen of forked tongues on this dragon char alone, before trading them in for the luck staff.
Second most popular weapon type are those claymore clones - black knight, Astora greatsword, boss soul greatswords etc. They are very similar imo. That eastern curved greatsword is popular too.
Hammers, axes and spears are nowhere to be seen. No more than 1 of 10 are using those.
"Super heavy" weapons are rare too. There are a few who knows how to use them, but I imagine that sky high str/dex and weight are too intimidating.
I had a fight with a guy who used a "normal" Greatsword, and he was very good with it - killed me twice, and I felt powerless against him.
Yeah, and almost everyone is using a fire buff before the fight. Magic on rare occasions. A few used dark, but never lightning. Seriously, haven't seen lightning bolts being used a single time in PvP. although most shields and armor have shitty lightning res... Lightning used to be very popular in previous DS games.
That is of course my own experience, but I had, without a doubt, few hundred PvP encounters by now.