Studying the effect of an applied shear flow field is important for fine-tuning material microstructure. This is relevant mainly at interfaces with increasingly complex microstructures as they dictate the equilibrium and nonequilibrium rheological properties of multiphase nanomaterials. In this sense, block copolymers play an important role in suppressing slip and contributing to less efficient momentum transfer across polymer-polymer interfaces. This results in delayed film drainage times for two approaching droplets and could be used to control morphology. Hence, in this study, we perform a mesoscale Dissipative Particle Dynamics (DPD) computational study of how efficiently momentum is transferred across increasingly complex polymeric interfaces with symmetric surfactants of different molecular weights. This is also extended to rigid nanorod state-of-the-art Janus surfactants, which have been praised to be the next generation of polymer blend compatibilizers. Grafting these nanorods with polymers yields different interfacial microstructures. The way that these different interfacial microstructures dictate interfacial momentum transfer can be correlated to how droplets in a dilute polymer blend morphology coalesce or to how this mechanism influences flow-induced droplet coalescence. Moreover, the role of interfacial microstructure in stabilizing polymer blend morphology upon flow cessation is also assessed from the point of view of surfactant diffusion and spatial distribution. Thus, this study is important in many applications where multiphase flow is present, such as food processing and cosmetic applications and more clearly unveils the exact mechanisms through which Janus compatibilizers impact polymer blend morphology.