You are using the ‘Add torque in radians’ node. The unreal documentation says this - ‘Torque to apply. Direction is axis of rotation and magnitude is strength of torque.’
This means that the draw debug line is the axis about which your ball is going to rotate. Not the direction it is going to rotate towards.
Direction is axis of rotation. i.e. imagine the debug line is a pin or axle running right through the ball.
See what I mean?