Now that you've asked, I did some testing with the
"DUF Pose Converter" script for Poser 12+, and loaded some Genesis 1 and 2 DUF poses over Dawn2, and they worked pretty well. Only needs minor adjustments, which would be needed anyway if you used body morphs that change body proportions.
When it comes to G3/8/9, that's a different story because they are not TriAx figures, and also don't use traditional T-pose. Their rigging is more akin to that used in game engines, where there is only 1 weight map per joint, as opposed to 9+ used in TriAx, so the ball-joints (shoulders & thighs) require double bones, making this quite different from what we would expect. Converting those poses would be more a matter of adapting to a different rigging system, instead of just converting the file format.
For the time being, I will be releasing the "RigControl" script for Dawn2, which is covered in my dev thread here at HW. This was originally meant for posing only the face rig, but was now expanded to control ALL bones on Dawn2, to include regular bones, ghost bones, and ERCs (remote controls). It allows posing everything D2 has, and also creating facial posing presets with an interface similar to Poser's Memory Dots, but with additional features like custom captions and hover over thumbnails.