I'm a big fan of Marlene Dietrich; probably one of my Top 5.
Her career is patchier than Crawford's, but even longer: stretching from Silents to (indirectly) co-starring with David Bowie. Like Crawford, she had the ability to shift her imagery to suit changing times. I think she was at her best in her legendary films with von Sternberg, but I'm partial to her work in the early 40s. After reviving and recreating her career in DESTRY RIDES AGAIN (1939), she played witty floosies in several action-comedy films; my favorite being SEVEN SINNERS (1940).
She was apparently the second choice to play Margo Channing in ALL ABOUT EVE, after Claudette Colbert dropped out. She had played a similar part as a theater star in Hitchcock's STAGE FRIGHT. Zanuck was apparently keen on her, but Mankiewicz objected; he said she could pose beautifully but couldn't handle the film's dialogue. That assessment was both unfair but also kind of not. She gave some truly great performances throughout her career, but in so many of her films she hardly seems to try; she often seemed indifferent or tense, particularly in her lesser films.
This Tweet from BKR made me chuckle, because it's true: Dietrich took Old Hollywood stars' ability to self-mythologize to the next level. Her denial of her Silent film career fit into her self-created narrative that she was a young student when von Sternberg discovered her for THE BLUE ANGEL; she was in fact nearly 30. Even more brazen was when, in Maximilian Schell's fascinating documentary MARLENE (1984), she denied having a sister; such a curious thing to lie about.