I was maybe too young to catch the irony in this film when I watched it....am intending to re-watch all his films
Good luck in getting to see all his films
By the way, Hitchcock made a film called "Secret Agent" immediately before he made "Sabotage". That "Secret Agent" is not connected with the Conrad novel but that would be the reason why he had to re-name the following film as "Sabotage".
Of his very early films I've seen "The Lodger" (1927), "Blackmail" (1929) (noted for being the first British film made into a talkie), and "Murder!" (1930).
"Murder!" is almost experimental at times, some of it works, some of it doesn't. There's a scene with Herbert Marshall and Una O'Connor which is