This is not quite as extreme but A9T Vs Gunfisk lead - I always switch to Politoed, try to catch the rock slide. Some grass or flier comes in, I bluff a Blizzard, fire off WBs and aim for a farm down, at which point A9T can comfortably beat Gunfisk with plenty of energy or shield advantage. Done it so many times it’s just second nature now. It’s only tricky if the Gunfisk doesn’t through anything at Poli.
I did once take out a shadow Vic with Quagsire as the opp ended up bringing it out with shields gone (presumably realised I was running double water so didn’t take the bait) with Quagsire getting just enough energy to fire a SE before the final RL that would have KOed registered. That was scary but immensely satisfying