Notes in cues normally have the same stem direction, as cues usually highlight lines containing only one voice. Cues are shown by default with bar rests alongside them to indicate that the player reading the cue does not play those notes.
If cues contain music in multiple voices, the original stem directions of the source music are used. For single-voice cues, Dorico Pro determines the default stem direction depending on the pitches in the cue. Stems point downwards when most notes in the cue are at positions below the middle line of the staff, and upwards when most notes in the cue are at positions above the middle line of the staff.
Tip
You can override the stem directions of notes in single-voice cues individually.