While internationalization in higher education (IHE) is globally pursued, its underlying principles remain anchored in Euro-American epistemologies, often reducing Global South participation to peripheral alignment rather than meaningful collaboration. Introducing the Southern Epistemic Justice Framework (SEJF), a multidimensional model serves as both a normative lens and empirical evaluative tool to reconceptualize IHE through the principles of inclusivity, plurality, and reciprocity. Drawing on decolonial theory, sociology of education and curriculum studies, it proposes a triadic justice approach to assess internationalization policies across ten Global South countries: India, Brazil, China, South Africa, Indonesia, Mexico, Nigeria, Thailand, Egypt, and Vietnam. The SEJF Index is developed using panel data (2015-2023) validated through Pearson correlation analysis and variance inflation factor (VIF) testing across nine sub-indicators capturing structural efforts toward equitable internationalization. The mobility analysis uncovers diverse trajectories, revealing that reciprocity is the most decisive factor in justice-oriented reforms. Despite growing engagement, structural transformation remains uneven. This paper contributes a transferable framework for comparative benchmarking and equity-based policy design in IHE. It urges a shift from prestige-centric models to pluriversal, justice-driven internationalization inviting policymakers and institutions to view IHE not merely as global branding, but as a pursuit of epistemic justice and inclusive development.