Hello, thank you for the interesting question, I had to look this up myself!
There's a couple of ways you can do this using Custom CSS in your Customize -> Advanced -> Custom CSS & JS menu, but the only way I can think of to make sure that all of the email address links on your whole site do not have underlines:
This rule will remove the underlines from any email address link on your website.
Please keep in mind that for accessibility purposes, it is generally frowned-upon to remove the underline from links on your website. The reasoning for this is that if a user visits your website who is not able to see color, the underline is the only recognizable indicator that text might is a link.
I hope this helps!
Thanks, JesseIt works.
Customer support service by UserEcho