I don't think DS has that but maybe it could...

If you use Figure Mixer to combine Aiko and Laura, the resulting figure has a "Mix Type" setting which can be set to one of these (quoting the manual):

• Vertex Weights: When selected, uses DAZ Studio's vertex weights to determine the mixing of morphs.
• Joint Params: When selected, uses Poser's Joint Params to determine the mixing of morphs, however, it is not as accurate as using vertex weights and manual adjustments may be necessary.

But other than through Figure Mixer I don't know how you can use "vertex weights" with your figures. (this line shouldn't be indented)

It's not the tool used, it's the tool using it