Electric types are quick, Zebstrika no exception, and Dusk takes a hit after she tells him to Dig but before he's gotten safely underground.
The hit is -
"You're one of those, no straight-up power contests for you," she snorts, when Watson returns to his Pokéball of his own accord after Volt Switch and replaces himself with the Porygon-Z.
Dusk and the Porygon-Z "You" have a prolonged fight; You knows two offensive moves, one of which Sherlock knows better to use against a Dark type, and they're fighting defensively with plenty of uses of Conversion 2 to turn Dusk's attacks ineffective. Fortunately for Bella, no two attacks Dusk knows are the same type; if You turns psychic-type in response to Psychic, then next turn it gets a Faint Attack upside the head, and if it turns steel-type in response to that, she can order a Dig. Inconveniently for Bella, You also knows Recover. She doesn't resort to Dig after all, because You could recover more damage than the attack would do in the added span of time.
And of course it's getting in the occasional Tri-Attack through all this, and Dusk does not know Recover. Dusk faints, after Sherlock judges correctly that You can finish the Umbreon off in one more hit rather than spending the time on another recovery.
"You're good," Bella says as she releases Fireflower in Dusk's place.
"No more switching," says Bella. "Any more tricky bits up this one's sleeve?"
But as it happens, no. Unless you count Thunder Wave.
It's close. The Rapidash wins.
"Good match," approves Bella, patting Fireflower's burning mane affectionately and then returning her to her Pokéball. "I almost lost, that hasn't happened in a while without me taking massive handicaps."
Bella laughs. "Do you just hunt the wildlife for practice, all alone out here? I'd expect more straightforward strategy if that were it."
"Largely yes. And then of course there is Tony, when he can be bothered."
"Don't let him fool you—he's a brilliant strategist—but his team doesn't get much exercise unless I borrow them."
"Got his mind on other things?" Bella asks, sitting down on the ground and looking up at the sky. "That's fair, I'm just lucky that my project requires a team that can take me anywhere so I've got a good reason to focus on them much of the time."
"Looking for legends. That's why I'm here, it's supposed to have Uxie around somewhere."
"Nope, not a one. If this lake's a bust like Valor and Verity, I find another ace who's got Dive in their party moveset, we look at the bottoms of the lakes, if that doesn't turn up anything either I fly south, check Kanto and Johto and Hoenn."
"Some of 'em can talk, and they're all smart, smarter than even particularly bright ordinary Pokémon like Zag, so, first port of call is striking up a conversation. I want to figure out how and why they're immortal."
"To see if I can replicate it. I have to display a creditable effort towards beating the region Champ to remain a member of the Ace Trainers in good standing, but my endgame looks more professorial than like retiring to a little off-league gym on an island," she laughs. "Beating the Champ would just be for the international passport that sort of accomplishment buys; I'd be able to go anywhere."
"Well, after a fashion. Lots of hopeful flying to this location or that, hiking for days, finding rocks and plants and wild 'mon, and giving up and going back to civilization for a tournament or to visit my parents or to restock on potions."
"Yes," agrees Bella. "Yes, it would. So that's me; what do you do, besides keep your Pokémon and Tony's too in shape and play the violin? Or is that the sum total?"
"Eh, at least it's not just one thing, gotta be well-rounded."