As someone experienced a lot in unreal and somewhat in uefn I could help you build your project, at least from the coding and level building side. I’m not a 3d artist though so won’t be able to make character models and btw you can’t change directly character skins in uefn to custom ones, at least not without some ugly hacks (probably will change in future?)
I’ve worked on some fps vr shooters and stuff in the past