The command to conform a MetaHuman Identity by directly setting the template mesh is available from the Asset menu of the MetaHuman Identity Asset, and it’s called Configure Components from Conformed.
Conforming to a Template Mesh has very strict requirements to work well.
The mesh must be the MetaHuman Template mesh in terms of topology. This mesh can be obtained by downloading the source Asset (currently only available in the Bridge standalone application), or by using our DNA Calibration library.
Exporting a MetaHuman from the Unreal Engine editor is unlikely to work well as the exported MetaHuman would have some small but significant topological differences which are present between our template and the final MetaHuman.
Points on the mesh can’t simply approximate the volume. The semantic significance of the vertices needs to be preserved the way the automatic fitting would. For example, the edge loop that runs the nasolabial fold has to be used just for that and can’t be part way to the side of it. A neighboring loop can't be used instead.
Of particular significance are, of course, cardinal edge loops like all the various folds, the eyelids, the ridges of the ear, etc.
We recommend doing a first fit to your mesh with our guided process. Obtain the MetaHuman DNA from the resulting MetaHuman, and use DNA Viewer from DNA Calibration to obtain the starting mesh in your modeling application of choice.