Refer to figure.
A hovering turn is a manoeuvre performed at hovering altitude in which the nose of the helicopter is rotated either left or right while maintaining position over a reference point on the surface. The manoeuvre requires the coordination of all flight controls and demands precise control near the surface. You should maintain a constant altitude, rate of turn, and rotor RPM.

Counter-clockwise rotor: Initiate the turn in either direction by applying antitorque pedal pressure toward the desired direction. It should be noted that during a turn to the left the helicopter will descent if no power as added because left pedal pressure increases the pitch angle of the tail rotor, which, in turn requires additional power from the engine. To maintain altitude during a left pedal-turn therefore, power needs to be applied to maintain hover height.

During a turn to the right the helicopter will climb if power isn’t reduced because right pedal pressure decreases the pitch angle of the tail rotor, which, in turn requires less power from the engine. To maintain altitude during a right pedal-turn therefore, power needs to be reduced to maintain hover height.

Clockwise rotor: It should be noted that during a turn to the right the helicopter will descent if no power as added because right pedal pressure increases the pitch angle of the tail rotor, which, in turn requires additional power from the engine. To maintain altitude during a right pedal-turn therefore, power needs to be applied to maintain hover height.

During a turn to the left the helicopter will climb if power isn’t reduced because left pedal pressure decreases the pitch angle of the tail rotor, which, in turn requires less power from the engine. To maintain altitude during a left pedal-turn therefore, power needs to be reduced to maintain hover height.

When applying either right or left pedal for a hover turn you are effectively changing the positive pitch angle of the tail rotor blades collectively.

NOTE:
The answer can be confusing by the way it’s written with the term vary the collective positive pitch. However, they mean collectively changing the pitch of the tail rotor blades.