Like phantom3D said, MorphLoader Pro in DAZ Studio can do what you want.

I load the figure into Studio, pose it, and export the posed, welded and upscaled object to ZBrush.

Then I'm finished I export the fixed object  using MLP to convert it into morphs.
Finally I export the cr2 including the fix morphs back to Poser.

One drawback: Studio's and Poser's joint handling is (slightly) different.
The fix morphs made using Studio will work perfectly in Studio, but only "almost perfectly" in Poser.
So I usually need a little bit of additional MorphBrush work to "fix" the "fix-poses" for Poser.

Works quite well, but of course a "reverse morphing" system based solely on the Poser rigging (especially now that we can have multiple capsule shaped falloff zones) would be even better !

So if you'd write such a system for Poser, I'd definitely buy it !
(Hates bad joints !) ;-)