Costume Studio

Pick the packs: the hero body appears in its T-pose. Import 3D… a .glb / .gltf / .obj — it is fitted to the body, takes its bones' weights (or the body's) and moves with every animation.

For an exact fit: Body for Blender…, model the clothes on that body in Blender (parent them to its armature with weights, or leave that to this tool), export glTF 2.0 and import it here. Save writes the .msh, its material and the .dds textures.