This research investigates the relationship between cultural, social, and material attributes within entrepreneurial ecosystems (EEs) and their influence on the success of green startups, focusing specifically on comparative analyses between Brazilian and German contexts. Through a detailed examination involving the fuzzy cognitive maps (FCMs) and the fuzzy Delphi method (FDM), the study validates factors critical for fostering green startups. The research findings highlight the importance of business strategies that are culturally congruent and environmentally beneficial, focused on the unique characteristics of each ecosystem. In Germany, strategies emphasizing technological innovation align with a pragmatic environmental ethos, whereas in Brazil, community involvement and social innovation are more crucial. The study's methodological approach integrates expert opinions to prioritize the attributes that significantly impact green startups, revealing that strategic alignment with external ecosystem factors such as investment access, regulatory environments, and specialized talent is vital for startup survival and growth. However, the research faces limitations due to its geographic focus, potential expert bias, dynamic ecosystem characteristics, and the qualitative nature of data collection. These limitations suggest areas for further research, including expanding geographic scope and incorporating quantitative methods to enhance the robustness of findings. Overall, this study contributes to the understanding of how tailored business strategies, which can be developed through the analysis of the attributes and factors presented in this study, can support sustainable economic development in EEs contexts.