With the accelerating global carbon neutrality process and the increasingly prominent international green trade barriers, Chinese private steel enterprises are under growing pressure from mechanisms such as carbon tariffs and carbon credits. How these enterprises respond to carbon-related constraints, identify green opportunities in overseas markets, and transform them into sustainable competitive advantages has emerged as a key concern in both academic and industrial circles. This paper adopts a green affordance perspective and takes Huayuan Industrial Group as a case study to explore the process and underlying mechanisms through which Chinese private steel enterprises identify green opportunities via carbon footprint management. The findings indicate that the carbon footprint management process can be conceptualized in three sequential stages—carbon tracking, carbon reduction, and carbon trading, each shaped by the interplay between host countries’ environmental compliance requirements and the enterprise’s strategic green initiatives. As this process unfolds, green opportunity identification follows an evolving trajectory from informational affordance to technology-product affordance, and eventually to supply chain affordance. Furthermore, the mechanism of green opportunity identification comprises three interrelated and dynamically iterative phases: generation, perception, and transmission, each exhibiting distinct characteristics. The theoretical framework developed in this paper extends the explanatory scope of green affordance theory and offers practical guidance for Chinese private steel enterprises aiming to navigate global climate governance challenges and promote green, low-carbon, and circular development.