If you are coordinating with squad leader, and the the ship you target wants to do linked action, does both actions have to be on your action bar, or only the first?

Only the first.

Cool, this opens space for making coordinate usefull for scum. Zuvio with squad leader and tactical officer is only 39 points,

Remember that you're actually only coordinating the first action. The ship then has an opportunity to take the linked action based on that.

This also means you can't coordinate directly into the linked action.

So attack shuttle with squad leader can make X-wing do focus into boost, and B-wing to make focus into barrel.

2 minutes ago, Redblock said:

So attack shuttle with squad leader can make X-wing do focus into boost, and B-wing to make focus into barrel.

Assuming the X-wing has S-Foils closed, yes.

Technically, you're only coordinating the focus. The linked actions are triggered from there but are actually separate.

2 minutes ago, jftanner said:

Assuming the X-wing has S-Foils closed, yes.

Technically, you're only coordinating the focus. The linked actions are triggered from there but are actually separate.

Just as an addendum, the action linked to isn't mandatory. So you could coordinate the first action and the coordinated ship can follow up during its own activation with an action>linked red as long as it hasn't already performed either action already that round.