In Footrot Flats, The Dog sometimes adopts the persona "The Scarlet Manuka" and attempts to rescue abused Cricket balls, or Jess from her Bitch Box whenever she's in heat.
The Blackadder the Third episode "Nob and Nobility": Blackadder derides the public's obsession with the mysterious Scarlet Pimpernel, and makes a bet that he could rescue a French aristocrat just as well.
Wayne and Shuster: "Close Encounters of the Brown Pumpernickel Kind"
A quest reward in the Borderlands 2 DLC Captain Scarlett and her Pirate's Booty is a sniper rifle named "Pimpernel". It shoots bullets that explode into five smaller bullets, in a pattern similar to the petals of a pimpernel flower. If it spawns as an Incendiary rifle with no additional accessories, it's actually called the "Scarlet Pimpernel". Furthering the reference, its unique flavor text is "Sink me!", and it has a logo of two crossed swords behind a pimpernel flower.
In the Halloween Episode of Phineas and Ferb, every teenage boy in the city of Danville (plus Stacy) dressed up as the Scarlet Pimpernel.
The Pink Panther: In the short The Scarlet Pinkernel, the Pink Panther reads the story and decides to become a dashing hero.
DuckTales (2017): In "Friendship Hates Magic!", Mrs. Beakley is seen reading The Scarlet Pimperbill, which is seen to star an anthropomorphic duck version of the Scarlet Pimpernel. Launchpad sees the book and mistakes the title character for Darkwing Duck, a parody of The Cowl characters like Zorro and Batman that was likely inspired in-universe by the Scarlet Pimperbill the same way the latter two were inspired by the Scarlet Pimpernel.