As of my last update in September 2021, there are no widely recognized instances of One Nation One Election (ONOE) being successfully implemented on a national scale that have directly led to positive social change.1
References
1Vijay P. Harmonizing democracy: assessing the feasibility and implications of One Nation One Election in India. Journal of Legal Studies and Research. 2023;9(6):230-256. https://thelawbrigade.com/wp-content/uploads/2023/12/Dr.-Prasanna-Vijay-JLSR.pdf