Japanese convenience store operator Lawson Inc. has started requesting staff to wear a badge if they can speak a foreign language, aiming to cater to an increase in overseas visitors, the company said Tuesday. The badge covers seven languages — English, Chinese, Korean, Thai, Vietnamese, Indonesian and Nepali. Lawson said it chose them as the most commonly spoken by foreign tourists and based on the nationalities of Lawson staffers. Wearing a badge will be voluntary. “We hope visitors from overseas will be able to use convenience stores without any language barrier,” said a Lawson spokesperso…