Using Classic Outlook on Windows for personal email, calendar, and contact management
This is possible but not easy to find anymore. It is no longer located in the settings/options under display menu. You have to create a new message (not from a reply) find the format text tab at the top > Ellipsis > Paragraph > Show All.
There is a keyboard shortcut (CRTL + *) or (CRTL+SHIFT+8), however this does not work on reply messages either. You MUST be in a new message, in the body of the email for either one of these options to work successful.