I would like document changes in Word to show up in a different font colour

To change the font color of tracked changes in Word on a Mac, you can set the color for inserted text through the options available in the application. Specifically, you can use the InsertedTextColor property in the Microsoft.Office.Interop.Word namespace to define the color of text that is inserted while change tracking is enabled. If you set this property to wdByAuthor, Microsoft Word will automatically assign a unique color to each of the first eight authors who revise a document.

However, to ensure that changes are displayed in a specific color after accepting them, you may need to manually change the font color of the text after accepting the changes, as the default behavior does not retain a specific color for accepted changes. You can do this by selecting the text and applying your desired font color from the font formatting options in the ribbon.

This way, any users of the document will be able to see the changes clearly in the specified color.