Just one last detail...
Added 2021-01-05 16:36:50 +0000 UTC
New hair is ready, except I can't figure out what this issue is ٩(๑`^´๑)۶
But I will not give up... But posting here in case someone instantly recognizes the issue. It feels like I checked everything already (all maps, UVs, UV1, weights, mesh, edge cuts, etc.)

In Blender, nothing