I don't see Chrollo losing. He is far too intelligent and frankly Knuckle never fought someone of intelligence. Face him with Chrollo and it is over. Face him with Hisoka, it is over. Shoot's powers just aren't threatening enough to Chrollo due to his utter versatility. He would have far too many chances to steal either of their powers.
As for Nobunaga, that is an instant loss for both as he seems to have a limited en but a very fast attack speed. He would kill them if they got too close.
Feitan would probably be in trouble though, due to how he sustains damage readily to grow more powerful.
Franklin is a ranged fighter who is also swhole asf. I don't see them beating him once he notices them.
Machi's threads are versatile and she could easily thread them up, do something about Rafflesia pretty easily, assuming Shoot doesn't have access to his flying while standing on a fist thing. Then maybe she'd have issues.
Shizuku would vacuum up potclean and end APR. I assume she could do the same for the hotel itself. Assuming Blinky-chan can do that. She modifies it during the Chimera ant arc because she's absorbing blood from the spider ant but in Yorknew couldn't do that with living things, so far as I recall.
It only takes one Black Voice needle to end it all. But if they somehow avoid that, Shalnark must Autopilot, and he could vary well just instant-kill both of them before APR can do its work.
Phinks, same as Feitan, assuming he doesn't go straight for the kill. The Spider Enhancers are dangerous.
Uvogin would lose. He would waste too much time giving chances to both of them to cause serious harm. And if they stayed away after initially landing APR and Rafflesia, then it is over for him.
Hisoka (while he was technically in the Troupe) would be victorious, of course. Assuming he uses Bungee Gum intelligently like he did prior to the Chrollo fight, where he just... doesn't connect it right away. If fighting like he should be, Knuckle goes down instantly because APR does not work if the enemy counter attacks fast enough. And Hisoka would definitely do that. Easily. With Shoot, maybe they could do something, but likely Hisoka will just Bungee Gum the three hands, and then suddenly Shoot is useless and Knuckle is given the option of slugging it out or running. If the former, he loses, if the latter, Bungee Gum might yank him back. It is hard to say how tough it would be for Hisoka, as he'd do what Uvogin would, but I trust he'd immediately respond quick once he realized APR is some kind of bomb. No way he'd wait too long. He did pretty well against Chrollo and an entire horde of explosive people puppets anyway.
Illumi wins. Period. Plenty of needles and ruthless reflexes. Shoot could have been done in easily by Killua, and Illumi is far stronger than Kil, and won't hesitate when the moment is ripe. And he would be far more effective and in his natural assassin element within NGL. He would stalk them, then needle one of them in secret to control them, and then take out the other swiftly with the former comrade, assuming he doesn't just needle both to death, or use some other assassin ability, or go take an army of NGL natives or Gyro cultists. It would be child's play due to the environment setup. He'd have his choice of wild predators too.
