This is not something I can use in the Toobworld Dynamic; it's just something I found interesting.....
'MAN IN A SUITCASE'
In this episode, two actors teamed up who played Dr. John Watson of 221B Baker Street fame, one past and one future. H. Marion Crawford, leaning against the wall, was in the 1950s series with Ronald Howard as Holmes. A few years after this episode, Colin Blakely would be in the Billy Wilder movie "The Private Life Of Sherlock Holmes" with the master sleuth played by Robert Stephens.
As I said, I can't use this for Earth Prime-Time. Even though 'Sherlock Holmes' with Howard and Crawford was one of several incarnations of the pair before Jeremy Brett and David Burke/Edward Harwicke came along, that 1980s series is the official televersion. So that must be in an alternate TV dimension.
As for the Cineverse, that movie universe must have plenty of alternate dimensions as well in order to accommodate so many portrayals of the world's first consulting detective.
My thanks to the spy blog "Double O Section" for pointing this out......