Language is very important for an international business. A good and clear communication could never be possible if there is a language barrier.
You should be able to learn how to connect with people from every part of the world by speaking their language. It is only through establishing a multilingual company that you could be able to relate with people with different languages.
English is so far the most important language so you can be able to get by in many countries. But you will have an edge if your staff can speak any other languages.
Hire somebody who can help you negotiate with foreign speaking countries. You can hire staffs with diverse language and agree to communicate using English. You can pull them up once you needed a mediator for a client who speaks a foreign language.
An international company with multilingual environment can not only help you develop a good communication with foreign speaking countries, but also can enable you to expand your business amidst the language barrier.