For those working outside the English-speaking world, could there be some sort of glossary or guide to help with other languages? It might include useful phrases (that one is unlikely to find in a tourist's guidebook), key words for performers, and so forth.

Posters could solicit specific advice from native speakers (or others with the necessary language competency) to help make their performances more polished and friendly with local audiences.

Stories of performing in non-native languages would also make interesting (funny? terrifying?) reading.