While blockchain technology is widely touted as a solution for enhancing sustainability transparency in the luxury sector, its ability to influence consumer behavior hinges not on water-and-carbon data immutability alone, but on how that data is interpreted and delivered through retail channels. Drawing on survey data from 397 high-income luxury consumers in China and analyzed via Partial Least Squares Structural Equation Modeling (PLS-SEM), this study reveals that nearly half (48.67%) of blockchain’s effect on green consumption intentions operates indirectly through three mediators: retail marketing adaptation, perceived water-and-carbon transparency, and green trust (i.e., resistance to greenwashing). Once these mechanisms are taken into account, the direct impact of blockchain water and carbon disclosure is small and statistically fragile. These findings challenge the assumption of technological optimism and emphasise the key role of the retail interface (physical and digital), as water and carbon technology transparency becomes a place for meaningful action. We have proposed a comprehensive framework for luxury brands to embed the water and carbon environmental narrative supported by blockchain into specific channels and people-oriented experiences, so as to build credibility, reduce doubt and promote sustainable purchasing. Theoretically, the study bridges information systems and consumer behavior literatures by positioning retail marketing as the pivotal moderator of blockchain’s water-and-carbon behavioral efficacy; practically, it offers actionable strategies for aligning technological capability with market reality in one of the world’s most influential luxury markets.