Figura renders held items using its own item-pivot bones (RightItemPivot/LeftItemPivot), which cancels vanilla's item render pipeline before BetterCombat/PlayerAnimator's weapon-specific rotation ever gets applied. The result: your arm swings correctly, but the weapon itself doesn't rotate with the attack - stabs point sideways, slashes don't arc right, etc.
This mod bridges the two: it captures PlayerAnimator's per-hand weapon transform before Figura cancels the vanilla render, then re-applies it to Figura's item pivot matrix so your weapon actually follows BetterCombat's attack animations.