Sustainability transitions are shaped by specific dynamics, dependencies, and influences among the actors and elements that are part of the system. Systemic constellations as a social science research method can offer tangible visualizations of such system dynamics and thereby extract valuable, often hidden knowledge for research. This article builds on two online exploratory system constellation exercises about sustainability transitions, with two major objectives: (i) to introduce and disseminate (exploratory) systemic constellations as a method for (sustainability) research, and (ii) to extract their potential for (online) collaborative and transdisciplinary research, with a focus on sustainability transitions. Our exploratory research design includes participatory action research that took place during the virtual International Sustainability Transitions Conference 2020, Vienna, Austria. Data were analyzed following an interpretative-hermeneutic approach. The main findings consist of visualizations about sustainability transition dynamics between selected actors in Germany and Portugal that are discussed in light of the literature on constellation work and sustainability transitions, triggering new assumptions: (i) a strong sustainability narrative does not (necessarily) lead to action and transformation and (ii) transformation requires integrating narratives beyond weak and strong sustainability. We conclude with a list of potentials of exploratory constellations for sustainability research and online formats that offer novelties such as a constant bird-eye perspective on the system while simultaneously engaging with the system.