Fiber Shop 2 is a standalone real-time 3D hair creator, with export to .FBX as strands or ‘cards’. Version 2.2 is now available on a perpetual licence (it had been subscription) and at a reasonable $120 at present. There is a free non-commercial version which restricts the resolution of the texture-map exports and you don’t get things like the gradiated root-to-tip textures. Windows only.
What you don’t appear to get is a real-time “on the head’ view on a showroom-dummy head, it’s just the hair-cards that are previewing in real-time. You need to be able to round-trip to some 3D software that has actually built the hair mesh, so far as I can tell. I’m not sure if such round-tripping is possible with DAZ or Poser. Though it is with ZBrush and suchlike.
As for an art-AI to ‘add hair to a bald 2D render’ from DAZ or Poser, that’s still at the level of academic research papers so far as I can tell. But it’s doubtless coming soon.