Trewlove, speaking of the chess game, refers to "a variant on the Kronsteen gambit"; in "From Russia With Love", the Russian chess master played by Vladek Sheybal is called Kronsteen. Also, the large wall overlooking the chess game is decorated as a gigantic chess-board, just like the wall in the chess-match scene in the 1963 film.
Kent Finn mentions having gone to a redbrick university rather to Oxford, like Morse. He names it as "Lowlands", the fictitious university which is the setting for this 1980s TV series.
The near identical quotes by the pool supervisors. Character in Meganews: "In 1975, no one died. In 1976, no one died..." Character in Endeavour: "In 1959, nobody died. In 1960, nobody died..."