The concept of the metaverse, recently re-emerging in public discourse, is viewed by some as the internet's next evolutionary stage, while others regard it as a dubious promise of a future where physical and digital worlds merge seamlessly. As the metaverse takes shape, it is crucial to question whether its design will embody the values of the societies it aims to serve.

Cybernetic avatars (CAs) play a key role in Japan’s vision for Society 5.0 – a society where cyberspace and the physical world are closely intertwined to address social challenges. In-body cybernetic avatars, a sub-category, are remote-controlled micro-/nano-scale avatars or robots operating inside organisms, such as the human body. To explore future applications and implications of interactions with these technologies, we conducted an expert workshop (N = 16) in Japan. Experts co-created visions of a desirable future related to in-body CAs, identifying types of interactions, benefits, and potential risks. In a second study, we engaged an international student audience (N = 174) with three expert-developed scenarios to assess non-expert perceptions beyond Japan. We find that non-experts responded positively to all three types of in-body CA interactions. In addition, our study contributes to a better understanding of potential benefits and risks of in-body CAs from experts’ perspectives and sheds light on which factors are perceived as most impactful by non-experts.

Currently, the development of the metaverse lies in the hands of industry. Citizens have little influence on this process. Instead, to do justice to the pluralism of (digital) societies, we should strive for an open discourse including many different perspectives on the metaverse and its core technologies such as AI. We utilize a participatory speculative design (PSD) approach to explore Japanese citizens' perspectives on future metaverse societies, as well as social and ethical implications. Our contributions are twofold. Firstly, we demonstrate the effectiveness of PSD in engaging citizens in critical discourse on emerging technologies like the metaverse by presenting our workshop framework and participants' processes. Secondly, we identify key themes from participants' perspectives, providing insights for culturally sensitive design and development of virtual environments. Our analysis shows that participants imagine the metaverse to have the potential to solve a variety of societal issues; for example, breaking down barriers of physical environments for communication, social interaction, crisis preparation, and political participation, or tackling identity-related issues. Regarding future metaverse societies, participants' imaginations raise critical questions about human-AI relations, technical solutionism, politics and technology, globalization and local cultures, and immersive technologies. We discuss implications and contribute to expanding conversations on metaverse developments.