Hi,

I think the only way to achieve that is to change / inherit the source code. This logger is defined in the file base/models/ir_model.py, the method _reflect_model. You can just replace the lines with your own:

            if field.string in by_label:
                # comment -->
                #_logger.warning('Two fields (%s, %s) of %s have the same label: %s.', field.name, by_label[field.string], model, field.string)
                # add -->
                pass