Recognizing the environmental development-related commitments made by the Next Eleven countries at 26th Conference of Parties (COP26), this study scrutinizes the repercussions accompanying good democratic governance, renewable energy transition, economic growth, and the ratification of the Kyoto Protocol on carbon emission figures of these emerging nations. In this regard, the period of analysis considered spans from 1990 to 2018 while the econometric analyses involve application of both parametric and non-parametric panel data estimators. Among the key findings, firstly, the outcomes from the parametric estimation methods verify that establishing better democratic governance and undergoing renewable energy transition, both independently and jointly, curb carbon emission levels, while higher economic growth and the signing of the Kyoto Protocol are responsible for boosting emissions the Next Eleven countries. Secondly, the findings derived using the non-parametric methods reveal a great deal of heterogeneity when compared with the results obtained from the parametric analysis. Notably, better democratic governance is seen to reduce carbon emissions in less and moderately polluted. Next Eleven nations, while renewable energy transition curbs emissions only in the moderately and highly polluted ones. Additionally, these variables jointly inhibit emissions only in the Next Eleven nations that are moderately polluted. Besides, better democratic governance is observed to mediate the renewable energy transition-carbon emissions nexus only for the less-polluted Next Eleven nations, while the environmental impacts of economic growth and the signing of the Kyoto Protocol vary across different emission quantiles. Accordingly, relevant policies are recommended for helping the Next Eleven countries to comply with their pledges made at the COP26.