The following universes explored by Timmy and Ivan are:
A universe without Vicky
A universe where Timmy is a popular kid
A universe where Timmy dates Chloe
A universe where humans' and fairies' roles have been reversed
A universe where adults have fairy godparents.
The differences in the "B" universe version of Dimmsdale include:
Timmy is only slightly miserable, wears a blue shirt and hat, and doesn't have any fairy godparents. Also, he gets grades in school ranging from C to A and has a sister named Sophia, since his mother was pregnant with twins, and Mr. Turner decided to use extra money to buy stuff for boys.
Vicky's family is rich and lives in the same mansion where Trixie Tang would normally live in Timmy's home universe, while Trixie's family is poorer, and lives where Vicky would live in Timmy's home universe.
A.J. has a full head of hair and has an XK-91 computer.
Chester has Cosmo, Wanda and Poof as his fairy godparents, and has perfect teeth, although he doesn't use his fairies very often.
Tootie and Trixie Tang swap roles: Trixie is unpopular, nerdy, nice and always gushing over Timmy, while Tootie is popular, pretty, snooty, sarcastic and rejects Timmy most of the time.
Contrast to Timmy's home universe where Vicky is a mean babysitter and Tootie is her nicer sister, parallel Tootie is a sarcastic and sometimes mean young sister, while Vicky is a really nice and caring babysitter. Parallel Timmy sometimes thinks of parallel Vicky as his alternate mother figure.
The Dinklebergs in this universe are shown to be friends of the Turners. Sheldon Dinkleberg is a police officer and Daran has no grudge against him.
Notable things in genderbent Dimmsdale:
Timmy and Timantha are exactly the same, except with swapped personality traits, swapped ages and have each other's skin tone.
Ricky and Vicky switch roles. Ricky is Timmy and Timantha's sadistic babysitter, while Vicky becomes Ricky's girlfriend wished by Timantha and Timmy to distract him, which backfires when the Turner parents offer them double pay. Timmy and Timantha later set Vicky up with Nigel-Night (gender swapped Dolores-Day), a seemingly rich and handsome guy who turns out to be an old man and Denzette's father, as a reference to the episode "The Odd Couple".
Some of the parallel Dimmsdale character counterparts are similar to the episode "It's A Wishful Life".
Like the crossover episode "SpongeOdd SquareParents", this episode reunites Carlos Alazraqui, Tom Kenny and Mr. Lawrence, main voice actors of another Nickelodeon series, Rocko's Modern Life.
Nancy Cartwright, the voice of Trixie's male counterpart, Troy Tang, also voiced Chuckie Finster in Rugrats and All Grown Up (after Christine Cavanaugh, Chuckie's original voice actress, retired). Chuckie's adoptive sister is Kimi, who is voiced by Dionne Quan, Trixie's original voice actress.
One of the alternate universes shown was Timmy dating Chloe instead of Trixie or Tootie, which is a reference to fans shipping Timmy and Chloe.
One of the alternate universes shown is a universe where Vicky was never born, referencing the episode "It's a Vickyful Life", where Timmy wished to see a world without Vicky.
One of the alternate universes shown is a low resolution universe, which has poor animation quality and every character there is speaking in a loud tone, poking fun at the inferior animation quality and the characters tone of speaking in the second half of season 10 of the Fairly OddParents and the dialogue throughout season 10.
Originally, adults having their own fairy godparents was planned to be a subject of a short on The All New Fairly OddParents! Shorts, before WikiaIvan1997 decided to scrap it and use the plotline as one of the alternate universes.
FLCL - The manga universe scenes are similar to the manga scenes in the FLCL anime.
Reno 911! - In one of the alternate universes, Sheldon Dinkleberg is shown to be a police officer, similar to Reno Sheriff deputy James Oswaldo Garcia from Reno 911!, who was played by Sheldon's voice actor, Carlos Alazraqui.