Press Sear/Sauté on the Multicooker, adjust the timer to 15 minutes, and let heat for 3 minutes.
In a small bowl, combine the ketchup, honey, and mustard. Set aside.
Add 1 tablespoon of the olive oil to the pot and heat for 1 minute.
Season the pork with the chili powder, cumin, and 1/2 teaspoon each of the salt and black pepper.
Add the pork to the pot and cook, turning occasionally, until browned on all sides, 5 to 7 minutes total. Press Cancel.
Scatter the onions in the pot, drizzle with the remaining 1 tablespoon olive oil, and season with the remaining 1/8 teaspoon each salt and black pepper. Lift the pork and set it on top of the onions. Spoon half of the ketchup mixture over the pork.
Cover with the lid, press Bake, and adjust the temperature to 400°F and the timer to 15 minutes. Cook until the pork registers 145°F on an instant-read meat thermometer, 10 to 12 minutes. Press Cancel.
Transfer the pork to a cutting board, spoon the remaining ketchup mixture over the top, and let rest for at least 5 minutes before slicing.
Transfer the onions to a small dish and serve with the pork.