To address part of the puzzle on China’s ideational impact in the era of the Belt and Road Initiative (BRI), the article studies social interaction of Chinese and CEE think tanks by employing the concept of diffusion of ideas. The article proposes a theoretical framework to study diffusion inspired by reflexive social science that focuses on frames, (geoeconomic) imaginaries, and translations. The asymmetrical interaction of think tanks led to aligning the frames of the different actors and producing a context of peaceful and pragmatic cooperation, extension of the geoeconomic imaginaries to include previously unorthodox positions, and translation of policy concepts that are localized in accord with the dispositions of the CEE actors involved. Nevertheless, the China–CEE think tank cooperation, when analyzed in a broader context, has relatively limited impact on societal and policy levels, and is increasingly challenged by actors with greater leverage in the region. What sustain the diffusion of ideas are the potent narratives of imagined futures of prosperity under the New Silk Roads.