Especially if you’re going for an int build you want a swash base over fighter. Personally I think wounding critical (swash 19) is the best swash ability. Non crit immune opponents just melt to it. Particularly if you’re using a rapier and take improved critical, or use a wet stone.
So you probably want to get to swash 19. The question is, do you want 4 rogue for skills, evasion and uncanny dodge leaving you at 7 duelist?
Uncanny dodge would be very helpful vs multiple opponents so you don’t lose all that defense. However going to 10 duelist would give you another d6 on precise strike, 3 more AC, and more improved reflex uses.
You also lose 2 grace and 1 dodge AC not going to swash 20.
So swash 20/duelist 10 is legit but you lose evasion, uncanny dodge and skill access. You’ll have more 1 vs 2 AC but also no expose weakness.
Or you could go 16 swash/4 rogue/10 duelist and have weakening critical but not wounding critical.
I’d probably do 19/4/7 but honestly any of those will be just fine in pve and all of them will lose to casters in pvp
so play whatever build is the most fun in that regard.
You want a pretty high dex for AB and Int for damage. I’d also dump strength and pick up combat insight in epic levels to double your int bonus to damage. If you go for 10 duelist can get AC up to 30 int. 7 duelist means 24 int will give you max AC. That’s pretty easy if you grab a +4 int helm.
So you’ll be splitting dex and int. Slightly higher dex gives more AB, slightly higher int gives more damage. If you built two similar characters side by side and one had a slightly higher dex while the other has a slightly higher int you probably wouldn’t notice the difference.
The rouge build gives you access to expose weakness and you’ll need epic prowess for combat insight anyway. You’ll have plenty of AB so it’s not necessary but with a decent dex the bleed does add up over time.
I’d definitely pick combat expertise, deadly defense, weapon focus rapier and improved critical rapier, and of course dodge and mobility to qualify for duelist. Some people will argue that you don’t need to spend a feat on improved critical because of wet stones or keen wands but it sucks when you get dispelled.
Lastly this is best dine with a drow because of coolness and racial superiority
so play whatever build is the most fun in that regard.
