Though we haven't seen the extent of Chrollo's abilities, I think we can safely say he'll lose without posing too much of a difficulty.
Firstly, Zeno Zoldyck stated that if Chrollo fought seriously, he might have defeated him. However, I don't see him beating Zeno too easily. If we go by that, Chrollo's only slightly stronger than Zeno.
Now, Netero's stronger(by quite a fair bit) than Zeno. At least, in my opinion. There's a reason why Netero took the King on alone, and did not hire assassins like Zeno and Silva to take him down. Imo, it was because they wouldn't have made a difference. The only one who could even touch the King in his opinion was him. And we all know how that turned out >___>
The King's much stronger than Netero, and therefore, Chrollo. He'll beat Chrollo rather easily, not with flashy Nen skills, but simply raw strength. Chrollo won't be able to put a scratch on the King.