I. Introduction
As wireless technologies develop at an accelerated pace, including the widespread implementation of the Internet of Things (IoT) [1] and the pervasive deployment of fifth-generation (5G) networks [2], the conceptualization and strategizing for sixth-generation (6G) mobile networks have already been set in motion [3]. It is believed that 6G can offer exceedingly high data transmission rates, which are important for digital twins (DTs) applications [4]. DT represents a cutting-edge concept in the domain of information technology. Essentially, a DT is a highly detailed digital replica or model of a physical object, system, or process, of which human digital twins (HDT) is one of the most popular DT topics and allows users to create an incredibly detailed, dynamic, and personalized model of themselves in digital formats. With an HDT, a person’s virtual representation can interact in a metaverse, just as the real person would do in the physical world, which could make virtual/augmented reality (VR/AR) experiences more immersive and realistic.