On forum I saw that 2h sword is 3% stronger than 2h axe in terms of DPS even after axe mastery buff from 60%-75%. To simplify things, can I understand that 3% difference as 142 atk axe = 137(=142*0.97) sword?
The simplified answer: For a Hero using Brandish (assuming infinite STR and Atk) Damage per STR(2h Sword) = (4.6+4.6*0.6)/2 = 3.68 Damage per STR(2h Axe) = (4.8+4.8*0.75+3.4+3.4*0.75)/4 = 3.5875 Sword/Axe = 3.68/3.5875 = 1.02578... Conclusion: Swords gain about 2.6% more Damage per STR. For fun here is 1h Spoiler Damage per STR(1h Sword) = (4+4*0.6)/2 = 3.2 Damage per STR(1h Axe) = (4.4+4.4*0.75+3.2+3.2*0.75)/4 = 3.325 Axe/Sword = 1.015625 Conclusion: Axes gain about 1.6% more Damage per STR For even more fun, let's plug some numbers for some arbitrary Lvl200 with decent gear Spoiler Perf+4 Claymore vs Dragon Axe, 1250 STR, 100 DEX, 50 cgs+others (mon, medal, etc.), Apple, SI, Echo, Attacking a Snail (or any other 0 def monster) (3.68*1250+100)*(285)*(1.04) = 1393080 (3.5875*1250+100)*(287)*(1.04) = 1368344.25 1393080/1368344.25 = 1.018... Conclusion: Claymore does about 1.8% better than Dragon Axe
The real comp should be 1h axe vs 2h sword. The 1h axe setup needs 11.3% more w.atk to be on par with the 2h sword setup which can be done with perfect shield and axe. Guardian proc marginally puts its over 2h sword in practical use. Not saying this is cheap, but definitely interesting theory crafting.
Sylafia's response is pretty much all there is to it, though it's quite likely that you will be able to acquire a significantly better axe than sword for the same cost, so 2h axe seems like a very viable option for folks on a budget -- even with other sources of attack factored in, a 3% difference is pretty small at earlier stages of the game relative to how much better of an axe you can get your hands on. Another small thing to note is the higher mastery (and brandish eliminating swing/stab rng in 4th job) means axes will be able to consistently kill mobs in a given number of hits earlier than swords, though this becomes irrelevant on higher hp content.