## 4 Final Considerations  
The use of immersive virtual reality and multiuser environment technologies may benefit industrial training by improving learning outcomes as immersion increases [17; 18; 44]. Our proposed method allows for the development of an immersive metaverse with a voice system and avatars, without experiencing any connectivity issues. We observed that even junior developers could understand the method, demonstrating that it is possible to develop immersive virtual worlds with an emphasis on professional training within six months of working with the Unreal Engine 4 tool, even without prior experience with 3D modeling or third-party licensing. Therefore, our proposed method has the potential to support industry in advancing projects involving immersive metaverses and other projects involving gaming engines and industrial training. As for this study's limitations, there are still several issues that must be addressed for successful metaverse development, which we did not detail. Future research into this topic could carry out a systematic literature review to map the current problems and the recommended guidelines to address them. Additionally, our study focused on a method for developing immersive virtual worlds for professional training purposes using the Unreal Engine software version 4.27.2. While other game engines such as Unity and GoDot can also be used to develop VR applications, our proposed method using Unreal Engine software version 4.27.2 can provide benefits such as better graphics quality, more advanced physics simulation, and better support for VR devices. Future research could explore the use of other game engines and compare their capabilities and limitations in developing immersive virtual worlds for professional training purposes. Regarding the advantages of using the Unreal Engine software version 4.27.2 over other game engines, the software's latest generation technologies such as Lumen Global Lighting System, Virtual Shadow Maps, Hardware Raytracing, and MetaHumans can provide significant benefits in terms of graphics quality and realism. However, the hardware of Meta Quest 2 still lacks the capabilities to utilize these new features of Unreal Engine 5. Additionally, Unreal Engine's software version 4.27.2 better supports VR devices, making it easier to develop VR applications that are compatible with a wide range of HMDs. Also, high-end HMD displays such as Varjo XR-3 or Valve Index can provide significant benefits in terms of resolution, field of view, and overall visual quality. However, our method can still provide benefits even with more affordable HMDs such as the Meta Quest 2, making it accessible to a wider audience. Future research might also validate our proposed method and explore user experience and user interface design in immersive metaverses. This could involve increasing the number of developers participating in the experiment since the number of developers using the Unreal Engine software tends to be lower than that of similar software such as Unity, and making a comparison between the two main software platforms in terms of immersive metaverse development. Another requirement is to determine in real-world industry training sessions whether using virtual reality technology in conjunction with the metaverse can improve information use and memory retention. This validation could also enable a comparison between physical industrial training and virtual immersive exercises. This comparison may create a new need for research on user experience and user interface (UX/UI) applied in an immersive metaverse and how they may affect user quality and usage. An in-depth investigation of this issue may lead to better uses of the technology beyond industrial training, including any application that makes use of immersive virtual reality technology in metaverses. **Author Contributions:** Conceptualization, L.G.G.A. and M.F.C. ; Methodology, L.G.G.G.A., I.W. and M.F.C. ; Software, L.G.G.G.A. and M.F.C. ; Validation, L.G.G.A., I.W. and M.F.C. ; Formal analysis, L.G.G.A. and M.F.C.