My position on the question word posters is that they should be only written in English. There are two reasons for this:
(1) if you point to the word and say it in the target language, with its English translation next to it, the students tend to tune out the word in the new language. Why should they process it in a language that they don’t know when they can just do so in a language they do know?
(2) pronunciation problems can arise later when you use dual language question word posters. If the students see “quand” (when), then they may tend to say it phonetically as “qwand” and so mispronounce it.