I'm not sure if this has been done or not because I haven't seen any Western themed AUS.
But my idea was that this Outlawtale/RedemptionTale AU is taking Inspiration from Red dead Redemption.
They are on the run from bounty hunters, which are humans.
Our Outlaw gang is called The Dreemurs.
Asgore is of course the leader of this Gang. He's weapon would be a shotgun. His horse would probably be an Arabian or a Shire probably. (My knowledge of horses is limited to the RDR Games). I can also see Asgore smoking a pipe and being the one handling this gang.
Toriel as Asgore's wife will be as always the mother of the gang. She, Muffet and Grillby are taking care of cooking and cleaning in the gang. I can also see Toriel taking care of sick and also teaching/rising the kids in the gang. Although I imagine Toriel not wanting the kids to become outlaws as well.
Sans is lazy as always this won't change. Most of the time he is sitting against a tree and napping. But occasionally he's getting send on the missions where you have to be quiet like breaking into a bank, breaking into some house and stealing valuable things. Sans is dual wielding two pistols, according to Sans they are easier to clean. I imagine Sans rarely using the horse and yet he somehow always arrives faster then the others at the destinations.
Papyrus and Undyne are the hunters of this gang, which is a terrible idea because they both are scarring every animal and yet somehow manage to catch some. Undyne's weapon would be a spear (for hunting) and dynamites/Molotov cocktails (yes she has tried to hunt animals by throwing dynamites at them. Undyne and Papyrus are usually the reason why the gang has to move from place to place sometimes.
Papyrus weapon...hmm I can see him having multiple guns, but he mostly uses a pistol. The times when he hunts alone...he actually gets more game then with Undyne. I can see Papyrus also taking care of the horses (perhaps other animals). He always scolds Sans for being lazy and forces him to help him, but Sans usually finds excuses to not work.
I can see Undyne's horse either being a Shire or a Thoroughbred. Since things tend to explode around her she needs a worse who is not afraid of it.
As for Papyrus...hmm...I can see him having a Mustang. I imagine Papyrus wanted an Arabian because its the best horse (based on the stats in RDR2) and Papyrus has high standards! But one day he saw an owner abusing his horse and he tricked the guy before stealing the horse. Since then he has his loyal Mustang.
Alphys and Gaster are gathering herbs, making medicine. They are making sure the gang always has what it needs. If they notice the Gang lacks something like dynamites (because Undyne took all of them) they are the once going into the town and buying the stuff. Well its usually Gaster, because Alphys is nervous around peoples. Alphys sometimes asks Undyne to do it, which is a terrible idea it always ends in Undyne getting in fights with someone.
Mettaton is still a celebrity as he earns money through making shows and theatre. He also uses his charm to trick people into giving him money. But he refuses doing any dirty work. He doesn't have a horse he insist that the others drive him with a carriage.
I can see Asgore smoking (only pipe), Sans (he hides it from Papyrus because Papyrus hates it), and Gaster smoking.
Undyne is not allowed to go into Saloons because its always ends up in a brawl.
For some reason I can see Undyne be at one hand I can imagine Undyne being one of the strongest fighters, but I can also imagine her being a big headache for Gang.
-Undyne no!
-UNDYNE YES! (Proceeds to throw dynamites)
I also can see potential for Outlawswap/Redemtionswap and Outlawfell/Redemptionfell versions.
