If you're intent on complying with the law, no matter how stupid it may be, visors won't do it.Still no word on the use of visors! Hopefully things will be clearer by Double Trouble and I might see you then.
"Face visors, shields and transparent face coverings
A face visor or shield may be worn in addition to a face covering but not instead of one. This is because face visors or shields do not adequately cover the nose and mouth, and do not filter airborne particles."