The goal:

Exporting Millhorse with morphs and animations from Poser 12 to Blender 3.4.
In Blender I will add hair as mane and tail on the horse.
The final images/animations will be rendered in Blender and used in a game project.

What I have tried so far:

Exporting from Poser as fbx which resulted in loosing all morphs.

Exporting from Poser as Alembic (I read about that somewhere) which worked keeping morphs and animations. BUT when trying to add hair Blender gives error: "Invalid UV map... islands overlapping". I know what it means but I can not for my life figure out how to fix it.

Attached image of morphed horse with material rendered in Blender.

Any suggestions, links and hints would be much appreciated.