In an announcement on the Google Blog, Google announced that soon Google Assistant will be able to recognize different languages as soon as it is spoken. “We’re also making the Assistant multilingual later this year, so families or individuals that speak more than one language can speak naturally to the Assistant. With this new feature, the Assistant will be able to understand you in multiple languages fluently. If you prefer to speak German at work, but French at home, your Assistant is right there with you.”
However multilingual support will be somewhat limited at the start, where it will be only available in English, French, and German, but Google does plan to eventually expand language support to more languages in the future. In addition to being multilingual, Google will also increase support for other languages from 8 to 30. Note that this still means you’ll need to change languages manually unless you speak either English, French, or German.