Just a thought could a QRpedia scan with translation app be a down load option for people, the app could offer preferred language, plus an alternate language, the reader would check out those two language WP for an article; Once a person has the app they can make their own choices, modify language options as they want if neither is available then it offers a google translation from the local language to the persons primary language choice.
eg your phone is set to fr, sp you go into a museum in germany(de)
case 1 scan a qr code it returns an article off de:wp which is also in en,fr,sp you get fr version
case 2 its available in de, en, sp you get the sp version
case 3 its available in de only you get a google translation to fr