Its a simple fix, just Larian needs to add ambi-dexterous trait to the game. This feat removes the negative penalty associated with two weapon fighting- unsure if it exists in 5th edition thou. Regarding pathfinder, the way the game does it is it treats the secondary weapon as an additional source of damage and adds it as if it was any other damage source [force, acid, fire, frost, shock etc]. Do not know the math behind it thou. This could be added to BG3- yes swtor does it similar to pathfinder. The result would be not using off hand as a free action.
Is this Op? No its not. Enemies in BG3 will cheat by shooting through walls, drop things on you, throw hand fulls of bombs as if they are Elon Musk despite having no reason to have them, will use splash surfaces on effects, will actively try to alert enemies to you, will by a game of numbers toss you of walls to your death. [turning of Karmic dice does help, not sure why its on by DEFAULT]. You are already at a huge disadvantage [assuming your not cheesing, which i am not trying to]. This same issue is seen with DOS2. If you try to do tactician as it is designed your going to be slaughtered in 1000/1000 fights. Larian are even worse at balancing encounters then Paizo is at marketing pathfinder. This merely fixes a major disadvantage
