Hello,
Your project is similar to my completed project. You can check it here: https://www.freelancer.com/projects/PHP-Graphic-Design/Second-language-for-weebly-website.html
If you award me for your project, I will help you to build a multi-languages weebly site, and also build a script to check viewer's country and redirect them to their language. If the language is not available, the default language will be English or whatever you want.
Thanks.
Tuan Doan.