Plus there are low-recoil 12-gauge shells. Have the first shell be low recoil. In case that doesn’t do the job, have the rest of the magazine be full-power.
https://www.basspro.com/shop/en/winchester-aa-low-recoil-low-noise-target-loads-shotshells
Or you could just use an autoloader shotgun with full house rounds. For example, you can use the Saiga 12 as a giant one-handed pistol: https://www.youtube.com/watch?v=7WJoh6djzGo
Forgot this as required by internet requirements - cute girl firing Saiga 12:
https://www.youtube.com/watch?v=DNjTkUShaP4