Although Gary Illyes, a Google analyst, believes that search engines like yahoo might depend less on hreflang and more on automatic language detection in the future, for now, the tag is our best guess.  Adding this code to each webpage of your site is probably inconvenient and impractical, but most https://addons.prestashop.com/en/seo-natural-search-engine-optimization/31857-automatic-google-rich-snippets-json-ld-open-graph-seo.html