Humans Hold the Shield

To be honest I had forgotten about Fenris, shame on me, but he was something of a special case. I tend to think that the process that gave him his markings also gave him the strength to wield those incredibly large swords like he does. Also Denarius took the trouble to have him trained as a warrior. This may be true of other elves in Tevinter where historically slaves have formed the backbone of the army.

I was thinking more about elven culture in the south resulting in heavy weapon wielding warrior types, which is highly unlikely. City elves are not permitted to bear any blade larger than a knife and the Dalish focus is going to be more on hunter gathering and responding quickly to attacks on their clan. If they go on the offensive, they are more likely to engage in guerrilla warfare from the shadows.

I know PW has the clan training in conventional melee combat in Masked Empire under a "War Leader" but to be honest that makes little sense to me. I didn't play Witch Hunt so was not aware of Ariane's melee abilities.

The point about Iron Bull mentioning shields is a good one.   The thing is it would be normal to train a warrior in more than one style of fighting, so they can adapt to different situations.   You could actually imagine the Qunari employing the "turtle" when going into combat with mages or opponents with predominately ranged weapons as they certainly would have the strength to pull it off.   However, at some point the warriors would have to specialise in a particular style to make maximum use of the skills it gives.   Wielding a sword and shield requires a degree of self control to use successfully.  Whilst the Qun make a lot of their "discipline" and "mastery of self" they also seem to promote the idea that the ordinary rank and file are inclined to lose control when stirred up in battle, which is why you imagine they channel that raw aggression into the two handed weapon specialties.