While the integration of IoT devices in virtual spaces is becoming increasingly common, technical barriers to controlling custom devices in multi-user Virtual Reality (VR) environments remain high, particularly limiting new applications in educational and prototyping settings. We propose MetaGadget, a framework for connecting IoT devices to commercial metaverse platforms that implements device control through HTTP-based event triggers without requiring persistent client connections. Through two workshops focused on smart home control and custom device integration, we explored the potential application of IoT connectivity in multi-user metaverse environments. Participants successfully implemented new interactions unique to the metaverse, such as environmental sensing and remote control systems that support simultaneous operation by multiple users, and reported positive feedback on the ease of system development. We verified that our framework provides a new approach to controlling IoT devices in the metaverse while reducing technical requirements, and provides a foundation for creative practice that connects multi-user VR environments and physical spaces.