Yes. To change the text font (for example, color, size, family, and more) of your chat link (a chat button with Text Link type), you need to manually modify your live chat code before you paste it onto your website.

Followed is a sample about how to modify your live chat code. You only need to add the style attribute style="font-weight:bold; font-family:verdana; font-size:20px; color:#339999;" after