This was a Project I was working on (I did story, game mechanics and art) last year and almost got funded, but eventually never happened. I love languages, so i imagined the gameplay relying heavily on languages and communication.
Language Barrier
Speech Recognition Mechanics
Learning New Words
Understanding the other
Translating in another language
Co-operation
Communication
Understnading commands in different languages
Reacting accordingly
Win by adapting to every language