Beam placement relative to the staff
You can change the staff-relative placement of the stems within beams, so that beams appear on the other side of the staff to their default placement.
The default placement of beams relative to the staff is determined by the staff positions of the notes within the beamed group.
This means that the note furthest from the middle line of the staff determines the placement of the beam, although there are exceptions to this rule and other considerations that can influence the placement of beams relative to the staff.
Changing the placement of beams relative to the staff involves changing the direction of the stems in the beam. Therefore, Dorico Pro categorizes changing the placement of beams relative to the staff as a stem change.