Hi,

The Icon showing for the Size Guide is by default coming from the Theme end. So, there isn’t an option available to change that right now.

Alternatively, you can change it with custom CSS

.wd-sizeguide-icon>a:before {
    content: "\f080";
    font-family: arabic-indic;
}

But for that you need to know the content codes of the icons.

Best Regards.