On the webiste Courses offered – Studying (uni-mainz.de) you will find the updated list of subjects where there are no regularly offered English taught courses so the students need to have at least B1/ better B2 knowledge of German to be able to get accepted.
SInce February 15th a new request form for freemovers is available
online until April 1st.
https://www.international-office.uni-mainz.de/freemover-en/ The students can find all updated information on the website.
For the form students need to register and then fill our the form. They need to
upload a Transcript of records, a motivational letter and also a language
certification for English and German (if they have skills). A list of
certificates accepted as well as links to free online tests are listed online.