No. The only rule is that their catchphrase/greeting is mostly a pun or a reference (for example, Whitney's greeting was once "Canis day end?" and Rudy's catchphrase was once "meowntain"; I have a poor sense of humor, I know)
I gave one of them "Hot Mess" as a catch phase when we first started...... each Villager uses it, along with other ones that we change when they ask. But, they ask each of us if they should change "Hot Mess" and we always always say no. They ask 2X a week, each Villager to each player (3 of us).
My (adult) daughter tends to give them nasty sayings, using the other language letters to get it thru the filters.
Generally I'll use "Allons-y!" as a greeting ("let's go" in French, and it was also the Tenth Doctor's catchphrase), but when it comes to catchphrases, I either keep it the same if it's one that I'm particularly fond of, or I'll put something adorable or something that fits the animal type/personality/look.
Never cruel or cowardly
Never give up, never give in
I can't remember many changes, but on New Leaf I gave Bunnie the catchphrase of DinoThundr [extend the limit in the Switch games please], and it stuck. She's never asked for a replacement and has never changed it. Maybe its her favourite as it is mine. Who knew Power Rangers existed in the Animal Crossing universe?
During football season, I get as many villagers to say #OnePride as possible - it's the Detroit Lions' hashtag.
I'm also fond of making them say bad words, but nothing nasty, just silly. Or I try to think of a pun that relates to the type of animal they are - Astrid the kangaroo currently says BOING! and Lionel the lion says RAWRRRR.
For greetings, since they only say it to me, I try to make it something that will make me giggle. Elmer is my favorite, so he says OMG, HI BFF! Boris wanted something that made him seem nicer, so he says Rainbows&Smiles!
Who would win in a fight, Indiana Jones or Han Solo?
I give all of my CF villagers catchphrases that match names of characters from my favorite book series. These include Theodora (Buck), Moxie (Bob), and Ellington (Gaston). Whoever knows what book series these three characters come from gets (imaginary) bonus points. As for greetings, I tend to say hello in other languages. Sometimes these are more common (Bonjour or Hola), but sometimes they're more unique - one character says hello in Pig Latin, and another says hello in a language my sister invented.
Cool. Cool cool cool. - Abed Nadir
Six seasons and a movie!
I used to make it a variation of their previous catchphrase in New Leaf but I just make it into little jokes like I made Inkwell's catchphrase "woomy" when he was at my town. For greetings, it was just the boring old "hello" but now it's the same situation as the catchphrase like I made Punchy's greetings "hoi".
I have no real set rule to it, but almost all my edited villager catchphrases have some kind of meme reference to it, for example, Croque says "else if", which is a line of code that well-known developer YandereDev consistently abuses. Chalice moment.
What do I do
with all of these
Mine say hello in certain ways depending on their personality. Basically, like this: Velma and Miranda: Hello there. Peck: Wassup? Chadder and Colton: Hiya! Chrissy: Hiya! also Deli: Hihi! Gaston: You again Pashmina: Heyooo!
Seek success, but prepare for vegetables - Inspirobot
1 hour behind ACC time!