With regard to Internet of Things (IoT) [ITU-T Y.4000], each IoT device may have a single or multiple unique identities in multiple IoT systems. Similarly, each IoT device also may have a single or multiple identities in multiple metaverses. An identity of an IoT device usually includes a unique identifier and a corresponding identity object [ITU-T Y.4811]. Although, it may take advantage of one IoT device having one unique identity in multiple metaverses, there are challenges; how those metaverses identify, authenticate and authorize the IoT devices when they roaming across metaverse platforms, and how the trustworthy shared storages interact with each other to support identity interoperability across storages. This Recommendation describes identity interoperability for IoT devices across metaverse platforms, and provides relevant technical features and reference framework.