please
I'm the uncreative
A DR AU where the heroes, main antagonist darkners and shadow crystal bosses are all switched places.
So DR's shadow crystal bosses (Jevil, Spamton, J. Eramovich, Gerson and Pink) would be the Fun Gang, DR's Fun Gang (Kris, Susie, Ralsei, Noelle and Berdly) would be the main antagonists , and DR's main antagonist darkners (King, Queen, Tenna, the Knight and Flowery) would be the shadow crystal bosses.
TLDR; every group's roles are swapped
Sorry if something like this already exists, I literally made it up this very moment after seeing your post.
Personality swaps!
Everyone's personality is inverted.
Also, LW<>DW<>LW swap.
So both have aspects of each other.
Berdly->Ralsei->Susie->Noelle
Ralsei is advocative and expressive
Berdly is studious and knowledgable, having vast knowledge of dark worlds; even more than most darkners.
Susie is shy and quiet from all the abuse at home.
Kris is colourful and talkative, and trusting.
Lancer wears a cloak and has a book, menacing and not talkative, replaces king fight
King likes lightners n stuff
Most of the ch1 darkners are confined to their homes, under the order of Lancer, who strictly mandates...everything.
With the exception of Jevil, who ironically thinks freedom is impossible.
Quotes:
*NO MORE, NO MORE!
*FREEDOM IS A LIE, THE JAILOR'S LIE!
*NO MATTER WHAT YOU DO, YOU CAN'T ESCAPE YOUR CHAINS, NO MATTER WHAT YOU DO! NO MATTER WHAT I DO!
*EVEN A KING IS A SLAVE!
[1][2]
Spamton is a helpful and honest pawn shop owner who you can sell items to. He hates salesmen, who he sees as greedy, and is optomistic, believing everyone is good at heart. (except people who make their living by lying.)
The KNIGHT is from the og dr, but began to feel regretful for their actions and managed to travel to an alternate universe. their only goal is to prevent the roaring.
Gerson is...complicated, I'll elaborate later but there's something relating to this au's KNIGHT counterpart.
Pink->Gaster. She watches over flower kingdom, making sure nothing goes anomalous. she's a physics doctor, and so is the ghost. they work well together.
carol->asgore. after "that day", she began drinking and was victim to a scathing divorce, eventually forced to live off selling flowers on the side of the road. she's kind though, and gives free stuff.
she's also a hippie cause yes
Rudy, now an only parent, works hard to make sure Noelle gets success in life. he can be a bit demanding sometimes...
Dess is on another continent, and climbing a mountain while looking for strawberries and calling home. her hair changes colour based on her dashes. when she reaches the summit, she can go home (she's kind of stranded)
Noelle is a slueth who pops up in unexpected places, looking for creepypastas. she's found "about 7 since she started, 6 of which weren't actually magic and scary."
Seam is a jumbly pile of optimistic nihilism. they give discounts depending on what you have equipped.
swatch has a mohawk and does music tours around the city.
sweet captain cakes are uptight managers for queen's butlers.
My guy you need to keep such great ideas to yourself 
Or maybe not... Well, this is your au after all, do whatever you want with it.
Variety as flowey
Also dess as mike and holidays as mike larpers
soniondgaster
everyone is 1% green AU
An au where your choices matter
Wait, no, that’s what I’m doing
This is good, also like the Celeste reference.
WHAT CELESTE REFERENCE?
LarpPanda: It’s right in front of you, dummy.
How about an au where you actually get your vessel
that alr exists
hmmmm hast thou heard of coloured text and typing quirks?
Yeah, why?
yea i made that au
They The M-Seam