In recent decades, European Union policies have increasingly supported technology-enhanced language teaching to foster multilingual and digital competences among younger generations (Council of Europe, 2018, 2022). Studies have highlighted the benefits of training teachers in digital storytelling to boost self-confidence and teaching skills in multiliteracies (e.g. Robin & McNeil, 2012; Özüdoğru & Cakir, 2017; Spaliviero, 2022). However, the effects of combining digital storytelling with multilingual education in language teacher training are still underexplored. This study examines the impact of a professional development course on multilingual education for teaching Italian in Argentina. The course involved 19 in-service teachers from various Dante Alighieri Societies, and included designing and implementing multilingual digital storytelling activities as part of an action research project (Cohen, Manion & Morrison, 2017). The research aimed to understand the potential changes in teachers’ self-efficacy beliefs and classroom practices (Borg, 2018). Students’ engagement and perceived learning gains were also examined in data collected by the teachers. The study adopted a qualitative approach and corresponded to a longitudinal case study, with data gathered through teachers’ diaries, focus groups, and students’ questionnaires (Yin, 2018). Results revealed that teachers felt more capable of promoting students’ multilingualism and intended to continue using multilingual digital storytelling. Although some resistance to technology-enhanced language learning persisted, students recognised the value of linking multilingual digital activities to intercultural topics.