Bodoro vs Gozu
I think Gozu. He looks a bit younger and stronger than Bodoro.
Flutter vs Ikalgo
Ikarugo. Flutter is only good at surveillance.
Bloster vs Franklin
Franklin. Because Franklin seems to also have some amount of brains besides brawl, while Bloster not. And I'm pretty sure, Franklin is faster and a lot more experienced, so dodging is an option.
Machi vs Biscuit
Ah, what an intersting one. I'd love to see this one. If Biscuit can land a punch, Machi is probably finished. But Machi is probably faster and her nen threads, while not exactly combat-oriented weapon, can very well shred her opponent's body if not carefully avoided... But I'll go with Biscuit as experience is on her side as well as the element of surprise when she switches to her true form.
Shizuku vs Cheetu
It'll be tough for Shizuku... Cheetu is superior in speed, clearly, but stupid, sucks at tactics and plays instead of fighting, while Shizuku, even if she's a ditz most of the time, demonstrated she can think and knows how to fight. So Shizuku in the end.
Colt vs Gorain
Goreinu. Colt seems weak, to be honest, and Goreinu, while clearly nowhere near the beast tier, has an effective ability that can even work against opponents a lot stronger than him (although probably they fall for his trick only once...), and it allows him to outclass weak opponents.
Gon, Killua, Meloreon, Kurapika, Ikalgo, Basho, Squala, Leorio Shoot and Knuckle vs all 10 Shadowbeasts
Although we saw the abilities of only half of Injuu, I think they're more likely to win. They weren't guardian dogs for mafia bosses for nothing, it's just Genei Ryodan even without Kuroro are slightly more than majority of even well-trained nen-users can handle...
Knife wielding Assassin vs Tsezguerra
Tsezuguerra. That assassin was able to see Kuroro's strike, sure, but seeing is not the same as possessing necessary reactions to do something about it. It does seem that the assassin didn't give Kuroro even the slightest of trouble, Danchou simply pinned him to the wall like a butterfly and let out his nen fish to finish the boring business for him. Well, sure, Kuroro is a beast who far far outclasses that nameless assassin (and Tsezuguerra), but still, it shows that the guy was nothing special. Tsezuguerra is a one star hunter (this has to count for something), cautious and rational, while he's not among the strongest, I'm sure he's not among the weakest either. He didn't fight Gensuru, but it's likely because Gensuru had a tricky ability.