Educational Digital Twins (EDTs) are emerging as a powerful pedagogical framework to accelerate the development of sustainability competences in engineering and architecture education. This contribution conceptualizes EDTs as interactive learning ecosystems that connect metrics (e.g., Level(s) indicators), values (the New European Bauhaus principles—sustainable, inclusive, and beautiful), and digital platforms (simulation, data-driven decision support, and collaborative learning environments). We present a comparative perspective between Spain and Chile, chosen for their cultural proximity and complementary strengths: Spain offers a policy- and framework-driven pathway aligned with European sustainability agendas, while Chile provides a context-driven approach shaped by resilience challenges and applied innovation in the built environment. Methodologically, the work combines a targeted literature review (2018–2025) with a SWOT–CAME strategy pipeline to move from diagnosis (strengths, weaknesses, opportunities, threats) to actionable measures (correct, address, maintain, exploit) in curriculum design, faculty development, institutional governance, and international cooperation. As a key output, we propose the Educational Digital Twin Readiness Index (ERI) to assess institutional capacity across four domains: (1) governance and policy alignment, (2) digital infrastructure and interoperability, (3) pedagogical and interdisciplinary capability, and (4) equity, accessibility, and inclusion. The resulting roadmap supports a replicable Ibero-American hybrid model that combines Spain’s regulatory robustness with Chile’s applied experimentation, highlighting open-source innovation, reduction of digital divides, and cross-border partnerships as enabling conditions for scaling EDTs in higher education.