This survey examines the roles of EMI, plurilingual, and pluripedagogical teacher training in shaping the language ideologies of primary and secondary EFL teacher trainees. It explores how these practices influence their knowledge and learning processes. Based on multilingual research and Swiss education language policies, the study reveals future EFL teachers’ perspectives on plurilingualism and its impact on their professional development and language competence. The results indicate a plurilingual mindset, with a preference for English as the medium of instruction due to the professional growth opportunities provided by plurilingual and pluripedagogical practices.