This article examines leadership and practitioner professional learning (PL) across two multi-school networks. This ethnographic empirical study involved the development of research communities comprised of teacher-led research projects in collaboration with academic researchers (ourselves). We explore what the impact this type of PL and our role as 'outsiders' had on developing teacher agency and teacher/leader identity, and how "leadership for professional learning" (LfPL) emerged through these research activities. Our research sites were a Multi-Academy Trust (MAT) and a Teaching School Alliance (TSA) in England. Ethnographic data were collected over a three-year period. Significantly, our approach to understanding the complexity of these learning contexts draws upon socio-cultural theory, particularly Figured Worlds to construct understandings of PL within an identity and agency framework. Further, it utilises the Bakhtinian concept of "outsideness" to theorise how knowledge is mobilised through these collaborations. This approach offers novel insights for conceptualising LfPL as the intra-actions and practices of our research participants as they mediate our entangled PL spaces as leaders, teachers and researchers, together with developing understandings of the complexity of academic positionality as 'the more knowledgeable other' among those who are actually in the know.