Mac OS X - Disable Automatic Underlining of Hyperlink?

I'm working on a standard email signature for our business. My manager wants a simple signature with Name, Title, Company/Division and contact phone numbers. I've formatted the signature with hyperlinks for email address (clickable name), web address (clickable company name) and phone numbers. I've reformatted all text to black and removed the underlines for linked text. Done! Not done.

When I paste the signature into the Outlook for Mac 2016 preferences, the linked text all pops up as underlined. I do the same in Outlook 2010/2013 in Windows and the underlines do not appear but the text is clickable. Even better, when I send an email from the Mac (underlined) to the Windows machine, the underlines disappear but the text remains clickable. On the flip side, if I send from the Windows machine (not underlined) to the Mac, the underlines appear.

I take it Mac OS is underlining the linked text automatically. Is there a way to format the text to prevent Mac OS from underlining the text? Is there a setting in Mac OS that I can't seem to find that can be disabled (for proof of concept)? I'm basically trying to answer my manager's question before it's asked - Can we display the signature with the links but without the underlines?