This article examined the possibilities and challenges in turning a top-down action research project led by high-level public authorities into a shared and collaborative, multi-sited and multi-professional bottom-up action research project. For this purpose, the article explored initial stages of a European level action research project called Linguistically Sensitive Teaching in All Classrooms that aimed to help teacher education systems to better acknowledge linguistically diverse student populations in seven European countries. The analysis of the data sought to answer how to promote linguistically sensitive initial teacher education by incorporating reflection tasks in the existing courses, and how to transform a top-down research project into shared and collaborative bottom-up action project. The primary data consisted of 19 video-recorded online research meetings. Qualitative analysis of the data was used to identify ‘critical moments’ in the data. These moments included a major insight where transformation of project related ideas took place. The findings showed that linguistically sensitive teaching as a phenomenon was found to be complex and the related terminology challenging to translate between languages and contexts. Furthermore, a European level action research requires negotiating a joint understanding about the roles of the participants and the individual perception of project ownership in each context. Therefore, the findings indicated that a deeper understanding of the processes of participation and the partnerships involved in the action research may be as valuable first step in securing a systematic change towards linguistically sensitive teacher education as the actual reflection tools developed in the project.