To do Alt + H + S + O on Mac in PowerPoint, download and install Accelerator Keys, then press Option, followed by H, S, then O.
Command: Shape Outline Menu
This is how to do Alt + H + S + O on Mac in PowerPoint with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with PowerPoint.
Alt + H + S + O opens the Shape Outline menu, providing options to change the outline color, remove the outline, or adjust weight, sketched style, dashes, and arrows for the selected shape’s border.