Correct skeleton imports, though what to do with re-parenting and skeleton impurities such as effector nulls still uncertain

addons/io_scene_swbf_msh/msh_model_utilities.py

@@ -5,6 +5,16 @@ from .msh_model import *
 from .msh_utilities import *
 from mathutils import Vector, Matrix
 
+
+def convert_vector_space_(vec: Vector) -> Vector:
+    return Vector((-vec.x, vec.z, vec.y))
+
+def convert_rotation_space_(quat: Quaternion) -> Quaternion:
+    return Quaternion((-quat.w, quat.x, -quat.z, -quat.y))
+
+def model_transform_to_matrix(transform: ModelTransform):
+    return Matrix.Translation(convert_vector_space_(transform.translation)) @ convert_rotation_space_(transform.rotation).to_matrix().to_4x4()
+
 def scale_segments(scale: Vector, segments: List[GeometrySegment]):
     """ Scales are positions in the GeometrySegment list. """