Answer
No, it is not possible to rotate a scale bar using a specific tool in ArcMap. However, the scale bar can be converted to graphic that can be rotated.
Note:
Once the scale bar is converted to graphic, the scale bar is no longer dynamic.
1. Open ArcMap.
Note:
Ensure the map is in layout view.
2. On the main menu, click Insert > Scale Bar.
3. Choose a scale bar, and click OK.
4. Right-click the scale bar > Convert To Graphics.
5. Right-click the scale bar again to apply the desired rotation.