versatile weapon master

After deepening your understanding of the versatile properties of your weapons you have developed skills to use the property to its full potential, and you gain the following benefits:- 

when using 2 handed, you can double your ability modifier on the damage roll

while using single-handed you can use object interact action as a replacement of one attack or your bonus action once per turn (to swap weapons, shield or use magic items like scrolls )

you can also change your fighting style(from the ones available to the class) once per turn as part of the attack action once per turn.