Bimble's Bucket is very much is this to The Dreamstone, with a very similar dynamic, tone and even most of the characters resembling those of the previous show. Both shows take place in a fantasy world where an Evil Overlord desires the heroes' magical trinket, sending their bumbling minions with a Zany Scheme to steal it every episode. Both were projects created by Mike Jupp and Martin Gates Productions, meaning a good amount of the same people worked on both series.
According to Word of God, the Australian Preschool ShowBluey was meant to be one to the British cartoon Peppa Pig, intended as a replica of that program for an Australian audience (and depending on who you ask, not only succeeded at that but easily excelled past it). Both cartoons are about the funny Slice of Life adventures of a young animal girl and her family (with a younger sibling involved) and friends.
Then came Korean-Singaporean-Briitsh-Filipino cartoon Tish Tash, which is already a successor to Bluey for similar reasons that show is to Peppa Pig; just that now both cartoons are also about using the power of imagination to have fun.
In turn, Adventure Time and Regular Show can be considered this to the three above shows. J. G. Quintel worked on Camp Lazlo before creating Regular Show, while a number of SpongeBob and Phineas and Ferb writers eventually jumped ship to AT and RS.
Cow and Chicken, Ed, Edd n Eddy and Space Goofs to The Ren & Stimpy Show. Aside from the slapstick tone, the Avery/Clampett/Fleischer influences and adult humour, C&C shared most of of the crew on R&S, while most of the creatives on E-E-E had worked at Carbunkle Studiosnote Had the show been picked by Nickelodeon, it would have had the R&S crewmembers that did not join C&C, and SG's English dub featured Charlie Adler (Cow and Chicken) and Billy West (Ren and Stimpy) among its voice cast.
Like Voltron: Legendary Defender, The Dragon Prince has been considered to be one to Avatar: The Last Airbender. The fact that the show features Avatar alumni—Aaron Ehasz and Giancarlo Volpe on the production staff and Jack De Sena with a leading voice role (Sokka and Callum)—certainly helps.
The show can be seen as a spiritual successor to Gravity Falls due to both shows having similar premises of a bunch of kids living with their greedy great-uncle, and go solving mysteries on various adventures. It helps that both shows share some crew members.
Among Teletoon's works, we have Freaktown to Jimmy Two-Shoes to The Baskervilles. The former two share the idea of ¡Three Amigos! (a fun-loving Nice Guy, a dope, and a smart girl) in a town populated by monsters under the tyranny of a cruel ruler (and some lesser similarities) while the latter two revolve around upbeat humans in a Hell-like town ruled by a not-Satan trying to make everyone unhappy.
Generator Rex to the first Ben 10 series, both action-adventure Animesque series with sci-fi themes, secret societies, Body Horror, a hero with limited shapeshifting powers, and monsters aplenty, by the "Man of Action" team.
Hey Arnold! can be seen as one to the Nickelodeon movie Harriet the Spy. Both involve kids living in an unnamed big city resembling New York, adventures, eccentric kids in their grade, and eccentric people in the neighborhood. Makes sense, since Hey Arnold! was a theatrical short when the movie was released.
Llan-ar-goll-en also isn't without its comparisons to LazyTown, as both are cult classics from relatively obscure countries (Iceland and Wales) with a similar style of Medium Blending (one uses puppets while the other uses animated animals, both interacting with humans), and a great usage of Eccentric Townsfolk.
Mickey Mouse to Oswald the Lucky Rabbit: After losing Oswald to his distributor, Walt Disney created a new series of cartoons around a new character, Mickey, who was pretty much Oswald with the primary difference being that Walt owned full legal rights to Mickey.
My Little Pony: Rainbow Roadtrip through its general Lighter and Softer plot, animation, and theme, is effectively a G4 special that invokes the tone and style of My Little Pony (G3) rather than the parent Friendship Is Magic series. The plot is very simple and laid back Slice of Life fare, the stakes are nonexistent, and there's no villain or even an antagonist involved in this special whatsoever. It's as if it was designed as a deliberate love letter to the G3 series.
Ready Jet Go! is one to Sid the Science Kid, as both shows are PBS Kids shows that have a science-driven curriculum, and both shows star four kind-hearted, cute, curious children who just want to learn about science. It also helps that the creator of Jet worked on Sid as a story editor, and Jet premiered eight years after Sid.
Teen Titans Go! is this to Justice Friends, a series of shorts that aired between episodes of Dexter's Laboratory, which also starred a group of incompetent superheroes who were more interested in goofing off and getting into wacky hijinks than fighting evil.
In an odd case, TRON: Uprising is technically set in TRON: Legacy's timeline, but the tone and the relationship between Tron and Beck sets it as a "close enough" follow up to the sequel Legacy overruled — TRON 2.0
The Venture Bros. to The Tick. They share a creator/writer (Jackson Publick), an actor/voice actor (Patrick Warburton), and numerous themes (including various genre deconstructions.) Tick creator Ben Edlund is also the only person to write an episode ("¡Viva los Muertos!") of the Venture Brothers outside of creators Publick and Doc Hammer.
To the franchise of Avatar: The Last Airbender. It features many previous writers and artists from both Last Airbender and Korra, as well as the animation studio of the latter, Studio Mir. The characters have many similarities to Avatar characters; Lance-Sokka, Keith-Zuko/Mako, Coran-Varrick, Allura-Yue/Katara/Asami, Pidge-Korra/Asami/Toph, Hunk-Bolin, etc. The lions also represent the elements.
To ThunderCats (2011). Both are Animesque re-imaginings to popular cartoon shows from the 80's. Instead of just retelling their stories, they combine elements of their original series with Science Fantasy while giving the characters different backstories, personalities and motivations.
The ZhuZhus is essentially a successor to Littlest Pet Shop (2012), both being Canadian-American cartoons about a young girl who can talk to eccentric colorful talking animals. Helped by how The ZhuZhus started airing in the same year Littlest Pet Shop was ending (2016).