Here is how you can merge Detroit Become Human files to get them workable. 1st you need to find the skel file that goes to the mesh here is 1A5A skel. We only need .ascii file.

I use Notepad++ to merge these files. open up the skel and the mesh file. Copy all the skel file into the the .mesh file.

Now just remove the 1st set of bytes from the mesh file its usually a 0.

Save the file and use Noesis to load the mesh to check if everything is correct.