Hreflang" is an HTML attribute that helps internationalize your website by telling search engines what language you are using on a specific page. When it comes to implementing it in a sitemap, it's relatively straightforward.
Here's an example of how you might implement hreflang in an XML sitemap:
In the above example, we've specified two versions of the same page - one in English and one in German. For each version, we've used an
xhtml:link element with
rel="alternate" (indicating that this is an alternate version of the main content),
hreflang="xx" (to specify the language of the alternate version), and
href="url" (the URL of the alternate version).
Remember to include all versions of the page, including the page itself, in the list of alternates. Also ensure that every language version links back to all other language versions. That way, if a user lands on the wrong language version of the page, search engines can guide them to the right one.