You can export hair from Blender3D if you go into geometry Nodes mode and add one node: Realise Instances to turn the procedural hair into geometry hair. It will be a lot of poygons, though.  Another way is to extract edges in Blender from the scalp base, which is the old method.  If you are creating anime-style characters, freeware Vroid Studio has easy hair creation which can be exported as OBJ.  

Eternal Hobbyist