code: def move_layer_down(self):
          
          layer = self.list_layers_in_map_report.selectedItems()[0]
          index = self.list_layers_in_map_report.indexFromItem(layer).row()
          item = self.list_layers_in_map_report.takeItem(index)
          self.list_layers_in_map_report.insertItem(index + 1, item)
          self.list_layers_in_map_report.item(index + 1).setSelected(True)
docs: Move the layer down.