1. Load and then export a Genesis 3 fbx file to a folder. I just left it Fbx2014 binary. (edit - we don't need textures)
2. Upload the FBX to your Mixamo account
3. Apply an animation to your figure
And then Add to Assets. (I find that creating packs does not work for Daz later on - so do one animation at a time)
Download and ....Download- missing image but in the save options make sure fbx "with skin" is set.
4. Import your downloaded Fbx and choose mixamo.com option during import dialogue
5. Select your "imported" fbx g3 female and go to Edit>Copy>Copy figure
6. Select your Target G3 Figure/character and do Edit>Paste>Figure
7. Delete the fbx G3 version and set bones back to hidden on your remaining Genesis 3
The above method works ok if you want to apply an animation to any character (memorize/restore or apply figure shape after animation applied), although there is slight foot slippage
Alternatively, Instead of all the above, you could set all your morphs, add clothing, textures etc, export the fbx, upload all that to mixamo, apply an animation and just import the fbx back into Daz Studio and use as is. The animation should be quite solid that way but clothes may act weird.
And that's all folks! ......until next time