When writing a piece that will be published in multiple languages, are there any concessions a writer should make in tone, word choice, or style?

The piece in question aims to be accessible, informal, and conversational. A bit of slang strikes the right tone to my American ear. Will it come off alright to other English speakers? Will translators be able to deal with what might be called Americanisms? It’s literature for a self-help group. Translations are accomplished by members of a language community who work with a professional translator.