Creating an EdgeCollider2D with trail coordinates

Hi Guys,
I'm currently creating an Edge Collider 2D based on the coordinates I passed with the Player/GameObject.

My Problem is that the EdgeCollider I create is then off to the trail of the Gameobject (see Attached Picture with trail and green line). It also happens when I use directly the coordinates of the trail to create the EdgeCollider 2D. It seems it scales worse with higher distance. I also had to correct the starting position by subtracting transform.position. I assumed list pointList would contain Global Position Vectors and this wouldn't be needed. Is there any Position Concept I don't know/understand? The Script is attached to the TrailObject which is attached to the GameObject (a ship sprite). All Input would help me.

With best Regards, Markus

 private EdgeCollider2D col;
 private TrailRenderer tr;

 void SetPointsYourself()
     {
         pointList.Add(transform.position);
         setEdge();
     }
     private void setEdge()
         {
             col.Reset();
             List<Vector2> tempList = new List<Vector2>();
             for (int i = 0; i < pointList.Count; i++) {
                 tempList.Add(pointList[i] - new Vector2(transform.position.x, transform.position.y));
             }
             col.points = tempList.ToArray();
             col.transform.rotation = Quaternion.Euler(0, 0, 0);
         }