I assume that you want the names of the individuals? This is who I've identified so far: Morecambe & Wise; Max Miller; Queen Alexandra; Peter Sellers; Isambard K. Brunel; Terry-Thomas; Dickie Valentine; Tommy Cooper; Max Bygraves; George Formby; Arthur Askey; Sammy Davis jr.
The one you think is Queen alexandra will be a Music Hall star. A quick google tells me that Gladys Cooper, Marie Lloyd and Vesta Tilley all appeared there
If the lady in question isn't Queen Alexandra, and the ditto gentleman isn't Brunel, then their makeup artists have done a good job. I agree, Queen Alexandra and Brunel are unlikely to have played at the Chiswick Empire, but they are there, on the picture, and we are invited to identify them.
Well if you are convinced that's fine, But I cant see how it could possibly be them. As an aside I dont think the person in the top hat looks anything like Brunel. In dress or Facially. Ill leave it with you. Good Luck