Mercenary Contracts

[Pink]

I'm playing Gongsun Zan with the beta patch and I want to hire Zhang Yan to be a mercenary for me but I can't find any option in diplomacy to do so.

I was under the impression that all bandits could be mercenaries for other factions... or is there another requirement that I'm not aware of?

[Fried Noodles]

I've never tried hiring another faction to do mercenary work for me.
But playing as a faction that is capable of offering mercenary assistance, you're only able to float one contract at a time.
If the same rule applies to the AI then maybe Zhang Yan is already doing mercenary work for someone else.

[Emmental]

You have to be at war with the target. You can't hire a mercenary against a neutral or allied faction. That's the only requirement i can think of.

The actual section to do it is under the 'war' tab in diplomacy.

[Pink]

I only see two options regarding the contracts:

"Offer to turn against your contractor" => That I guess doesn't make sense because I can't be hired;

and

"Request mercenary turn against their contractor".

They are both greyed out but I guess its missing the option to actually hire him to be a mercenary?!