At USI in Lugano, Svizzera
Courses are entirely held in English, so this is the only language that is mandatory. Living in Lugano should be possible with only English, although learning the local language will make your experience more interesting.
USI offers courses in English, French, German and Italian free of charge for the entire USI community. Extensive information, including dates for intensive courses offered before the start of the academic year, is available here. Language courses do not count for credit towards your degree.
At FAU in Erlangen, Germany
Most of the courses are held in English, so this is the only necessary language. Since Erlangen is a student town, life is easy with just English knowledge.
FAU Language Centre (Sprachenzentrum) provides free German courses alongside regular studies for the students to learn German quickly and efficiently. The language courses are offered every semester and compacted into intensive courses during the break to help students catch up on the language.