Question COde:

• Makes a new mesh.

• Makes a new object that links to new empty mesh

• Links object to collection makes it active and selected

• Links the empty mesh to object again (new object is now context)

• Makes the bmesh and loads into mesh

Makes the mesh ok and adds a new object linked to that mesh to scene collections Ok... but it is not being transformed / aligned at all.

I dont get it tbh When i use object_data_add the location and rotation and align is just working fine on the second mesh that is placed ( let me be clear i want only 1 mesh to be placed) Why is it not working on the mesh i created? Im not talking about scaling but the 3 basic properties (location , rotation and align)

Because that is being done for you by the imported

AddObjectHelper and object_data_add

The function object_data_add is designed for use in conjunction with the AddObjectHelper class. Passed via the operator=self argument such that the newly created object can be aligned and transformed using the properties of the operator, eg if the new object is ob the code of object_data_add(...) could include

ob.location = operator.location

to position the object. The code is available to peruse 2.8x/scripts/modules/bpy_extras/object_utils.py

Changes

• Conformed to operator naming standard

• Removed un-needed imports

• Removed un-needed documentation links

• Changed around the methodology somewhat. The function add_plane_mesh() takes no argument and returns a mesh, regardless of operator or context. This makes it very re-usable, for example if addon is in a folder named "test_addon" could

      from test_addon import add_plane_object
  

  to use elsewhere. Moved object_data_add(...) into the operator's execute method conveniently with self and context as arguments.

Amended question code.

bl_info = {
    "name": "Test object",
    "author": "DGRL",
    "version": (1, 0),
    "blender": (2, 80, 1),
    "location": "View3D > Add > Mesh > DGRL",
    "description": "Adds a new Mesh Object",
    "warning": "",
    "wiki_url": "",
    "category": "Add Mesh",
}

import bpy
import bmesh
from bpy.types import Operator
from bpy_extras.object_utils import AddObjectHelper, object_data_add


def add_plane_mesh():

    verts = [(1, 1, 0), (-1, 1, 0), (-1, 0.9, 0), (-0.25, 0.9, 0),] 

    mesh = bpy.data.meshes.new("mesh") 
    bm = bmesh.new()

    bm.faces.new(bm.verts.new(v) for v in verts)
    bm.to_mesh(mesh)  
    bm.free()
    return mesh

class MESH_OT_add_object(Operator, AddObjectHelper):
    """Create a new Mesh Object"""
    bl_idname = "mesh.add_object" 
    bl_label = "Add Mesh Object"
    bl_options = {'REGISTER', 'UNDO'}


    def execute(self, context):
        object_data_add(
                context, 
                add_plane_mesh(), 
                operator=self)

        return {'FINISHED'}

def add_object_button(self, context):
    self.layout.operator(
        MESH_OT_add_object.bl_idname,
        text="Add Object",
        icon='PLUGIN')


def register():
    bpy.utils.register_class(MESH_OT_add_object)        
    bpy.types.VIEW3D_MT_mesh_add.append(add_object_button)


def unregister():
    bpy.utils.unregister_class(MESH_OT_add_object)        
    bpy.types.VIEW3D_MT_mesh_add.remove(add_object_button)


if __name__ == "__main__":
    register()