It would be quite fitting and fun to see Magikarp make an appearance as a rare fish in Animal Crossing New Horizons. Magikarp has the Animal Crossing sort of style and would make a great addition as a catchable fish! I believe Magikarp could make a great addition to the Animal Crossing New Horizon games both as reference and tribute to the long lasting and amazing Pokémon series. Magikarp has the sort of cutesie Animal Crossing style as well, so Magikarp would fit in perfectly!