Can my email footer use my website's social links?

Yes. In Email → Config → Footer, choose whether the footer's social links come from one of your websites or from a list you add by hand. When you point it at a website, every email reads the site's current links (the ones you manage in that site's Menu Layouts → Social section) at send time, so updating them on the site updates your emails too.

The links show as icons, each platform's own mark, and a link to anything else gets a globe. To show the platform names in text, set Show Social Links As to Names in text on the same screen.

When the footer follows a website, the website itself is the last icon, and its domain is the last line of the email. A website that has no domain of its own yet is left out.