The professional development of teacher educators faces critical challenges in transitioning from experiential learning to innovative paradigms. While traditional Professional Learning Communities (PLCs) provide platforms for knowledge transmission, their insular nature risks constraining individual creativity and ossifying knowledge reproduction patterns. In contrast, collaborative partnership models establish open learning environments characterized by permeable boundaries and polyphonic dialogue, effectively facilitating teacher educators’ boundary-crossing learning and knowledge innovation. Through four synergistic mediation mechanisms—consensus-building on developmental objectives, resource sharing infrastructures, co-constructed operational frameworks, and collaborative process governance—this approach enables a fundamental paradigm shift from vertical knowledge transmission to horizontal professional expansion.