Achieving the simultaneous improvement of environmental quality and export quality represents a critical breakthrough for countries pursuing high-quality economic development. Based on panel data for 67 countries over the period 1995–2020, this study investigates the impact of environmental regulation on export sophistication within the context of globalized production. First, this paper constructs an index of export sophistication from a global perspective and employs a Panel Smooth Transition Regression model to preliminarily identify a single-threshold effect of environmental regulation on export sophistication. On this basis, a baseline regression model incorporating the quadratic term of environmental regulation is established, and a series of robustness checks and heterogeneity analyses are conducted. The results indicate that, in both developed and developing countries, environmental regulation exhibits a significant “U-shaped” effect on export sophistication, although notable country heterogeneity exists. Compared with developed countries, developing countries display a higher turning point and stronger policy effects, suggesting that their micro-level agents possess greater tolerance for environmental regulation and that marginal changes in regulatory intensity exert a more pronounced influence on export sophistication. Furthermore, inspired by the theory of ecological fallacy, this study does not confine itself to the conventional dichotomy between developed and developing countries. Instead, it classifies countries according to their levels of export sophistication and conducts quantile regression analysis accordingly. The findings reveal that the impact of environmental regulation becomes increasingly significant and stable as the level of export sophistication rises. Only when technological capability reaches a certain threshold can environmental regulation exert a positive incentive effect; when technological levels are too low, they are insufficient to support the upward trend of the “U-shaped” relationship.

The coordinated development of ecological sustainability and high-quality economic growth has long been a central concern for both academia and governments worldwide. With the deepening of economic globalization, economic and trade interactions as well as policy interdependence among countries have become increasingly close. Therefore, it is necessary to incorporate cross-country policy interactions into the analytical framework examining the impact of environmental regulation on export technological complexity. Using panel data for 67 countries from 1995 to 2020, this study employs a Spatial Durbin Model to investigate the spatial spillover effects of environmental regulation on export technological complexity from the perspective of policy externalities. The results indicate that (1) regardless of whether countries are developed or developing, environmental regulation exhibits a significant “U-shaped” direct effect on domestic export technological complexity; (2) from the perspective of cross-border spillover effects, the impact of environmental regulation on other countries’ export technological complexity differs significantly across spatial weight matrices: it displays a “U-shaped” pattern under the geographical distance weight matrix, but an inverted “U-shaped” pattern under both the economic distance weight matrix and the nested spatial weight matrix. (3) Further analysis reveals that, compared with geographical factors, economic linkages possess stronger influence and explanatory power in the spatial spillover effects of environmental regulation. In other words, the process of global sustainable development relies more heavily on economic networks and industrial interconnections than on geographical proximity alone. (4) The heterogeneity analysis shows that the turning points of both the direct and indirect effects are generally higher for developing countries than for developed countries. This suggests that developing countries may have greater room for environmental policy adjustment during the process of export technology upgrading, while simultaneously facing a longer path toward green technological transformation. In light of these foregoing results, this study develops a series of targeted policy recommendations.