Mine are the Hisuian balls, specifically the Hisuian ultra ball. I just love the design of the latch, and the color palette used for all the balls. I especially enjoy the little flourish on the yellow stripes of the ultra ball!
What's your favorite? Any particular reasons why?
I have begun to recognize the power of the quick ball more and more recently. That and the timer ball, for those long drawn out "why won't you get in the fucking ball?!" fights. Looking at you, Iron Valiant.
That said, I'm not a fan of all the little clocks that pop out when I send a timer ball caught Pokémon into battle, so it's a last resort kinda thing.