The digital transformation that has been shifting the world has urged policymakers to look for tools that model this highly complex web of systems in a structured and easily understandable way to assist in designing better operating policies and guide effective change. System Dynamics, SysD (Forrester, 1971), is a recognized method for modeling and predicting the dynamic behavior of complex systems. In this research, we devise a way to convert SysD models into models in Object-Process Methodology (OPM, ISO 19450), a conceptual and computational modeling language and model-based systems engineering methodology. Using a real case study from the COVID-19 pandemic in Chile and other SysD models of disease spreading and patient caring, we have concluded that a fully automated conversion is not possible, because the SysD models contain implicit entities and assumptions that require the active involvement of a human modeler to interpret the SysD model for creating an elaborated OPM model. Yet, we found a set of SysD constructs that can be systematically converted into OPM constructs, and these help modelers translate SysD models and evolve them into high-quality executable OPM models that are both qualitative and quantitative.