Its completely pointless and horrible.
But, good declaration there. Again. Nice to see how far that previous statement about not wanting "hacks" actually goes and for what real reasons.

The point of wielding two weapons is... imagine that... - wielding TWO weapons. With different statistics, damages and effects.

Roguish build is one of the builds and skillsets in the game that could really use this to be more attractive. Instead of being limited only to backstabbing, and thus completely the same as any other rogue build ever made in gaming.

Which tends to become really, really boring as a gameplay style - in games that have hundreds if not thousands of combat encounters and you have to do the same bloody thing over and over and over.

Which is why Larian provided all those other Rogue skills and a separate Way of the Rogue specialization.
Which does look rather simplistic now, with just some very ordinary increases of some simple stats.

So my suggestion would be an excellent Way of Rogue unique skill, for example. Level two maybe?

Plus, my suggestion provides two different kinds of builds in this sense, one all attack and one with a bit of defense.
In combination one dagger + one Rondel. - while wielding two Rondels would not be possible -
In addition of wielding two daggers with different status and elemental effects.