we used to have the "Translate" button in wordpress - however this feature is not available in Xenforo because all modern browsers have plugins that do it for you - and even more convenient.
For Firefox (what I use) there is
You can configure it to automatically translate whenever you hit the site. You can also select the languages you understand to be "never translated"
For Firefox (what I use) there is
TWP - Translate Web Pages
Translate your page in real time using Google or Yandex.You can configure it to automatically translate whenever you hit the site. You can also select the languages you understand to be "never translated"