Handing of vertical curves in reports/table editor is always positive in the reports. Geometry exports are used by Construction Teams, as part of the Approved for Construction design pack.
Horizontal curves have a handing convention - +ve = RH curves. Vertical curves should have one too, +ve = Sag/Crest.
By adding a curve direction in a report can help eliminate possible errors in alignment implementation.
For reports, the information is available in the current software and is shown as the r or rate of change value. A positive r value indicates a sag curve (exit grade is larger than entry grade and a negative r indicates a crest curve. Since this data is already in the raw XML report data any XSL style sheet could be modified to format it differently on the report such as text indicating crest or sag curve or appending a + or - sign on the Length value.