 The study reveals a class of universal phase transitions to synchronization in keromotor-like models with both in and out coupling heterogeneity, using mean field theory to obtain analytical solutions for critical points and stable conditions for phase-locked states, demonstrating the influence of heterogeneity on dynamical properties and synchronizability. This article was authored by Kinshu, Stefano Boccholetti, Qigang Zhen, and others.