I don't know about other weapons, just to give numbers about crafted weapons:
At lvl 19, crafting/blacksmith 5, with the wetstone buff:
1H sword: 148-231 (+1max ap) or 155-243
1H axe: 148-262 (7%crit) 148-262 (+1max ap) or 155-275
Swords are eliminated at first glance, and assuming 10% base crit, a dualwield gives
2 * 205 * (0.24 *2 + 0.76) = 508 avg
vs
2* 215 * (0.1 * 2 + 0.9) = 474 avg
The crit bonus 1H axes are the best crafted axes, two of them do 508 per attack average, for 3 AP (at dualwield 5/5), which is ~170 dmg/AP.
This base damage is used for skills, most of which use 4 AP.
2H sword: 286-392 or 274-375 (+3 STR)
2H axe: 225-403 (+7%crit) or 234-420
At 10% base crit, +25% from 5/5 2H,
339 * (0.35 * 3 + 0.65) = 576
324.5 * (0.35 * 3 + 0.65) = 551 (+3 STR, which is less interesting if you put tormented souls since it doesn't stack).
314 * (0.42 * 3 + 0.58) = 578
327 * (0.35 * 3 + 0.65) = 556
The non crit 2H Axe is the worst usually, the swords are good early, and the crit axe is the best especially when you have load of crit (it becomes better and better).
578 damages for 4 AP is 144.5 damage per AP.
In conclusion, dualwield does more damage for auto attacks (17.5%), and 2H more for skills (13.7% for whirlwind, rush, and crippling blow which is available every round at 15 STR, and way more for flurry since theorically this skill only uses main hand).
Given the power of the crippling blow, I think it's hard to say which is best. I'd go for 2H personally, especially if you have a rogue dualwielder that need rare bracers/belt that give dualwield bonuses and good stats.
Be aware though that dualwield is far more reliant, as crit damage will go to waste (but can give good surprises too), and as it only requires 3 AP per attack (more streamlined).
Also, one advantage of duelwield is that you can swap slightly more easily to one-hand and shield when (if) the situation requires it.
Last edited by Chrest; 09/11/15 10:30 AM.