So myself and another member, davidhaus, worked on this list a while before wave 8 dropped and I have been running the list competitively ever since the ghost was released. I have seen a few double ghost lists pop up across different forums, but they have not placed well in tournaments and lack the proper tools to take on any and every build that might show up across the table. Me and davidHaus wanted to create an orignal ghost list that most would not expect to show up on the table and do well. This list not only has double ghosts, but also a Prototype Pilot A-Wing w/ the Chardaan Refit upgrade (15 points). Here is a link to the original list: https://geordanr.github.io/xwing/?f=Rebel%20Alliance&d=v4!s!157:36,120,-1,-1,160,97:-1:-1:;158:36,-1,-1,-1,164,165:-1:-1:;32:72:-1:-1:&sn=Ghosts%20on%20Target%20Mk.%20I
Prototype Pilot: Lynchpin of The Double Ghosts-
Believe it or not, many times, the success/failure of this list hinges on the A-Wing, especially in this scouts/Palp aces/Dash-Ghost meta. As I have told others who have seen me run this list, the ONLY job of the A-Wing is to be a nuisance and block every chance it has. If I think it has a block, then I'll give it an evade action, or (rarely) use the boost action to secure a block. Blocking is THE primary objective for the A-Wing as long as it lives because it denies the enemy ships their actions and THAT is the ghosts' defense. If my A-Wing can't block or it misses a block, then that is more than likely 3 or 4 unavoidable hits my ghosts are taking from an enemy ship.
As we all know, the ghost has an evade action for defense, but I almost never use it for these reasons: 1. Hera/Ezra loves stress! I'll pull red maneuvers all game long with this ghost and land on or pass over debris clouds as well without a care, piling up to 10-20 stress tokens throughout the game. 2. The ghost with Dash crew doesn't care about landing on asteroids(in the combat phase)! Many games, I'll try to avoid them so I can take a focus token to maximize damage output, but when I can't or I don't want to, I'll gladly overlap or land on a rock. I may roll a hit for the asteroid, or I might not, I have 16 HP on this ship 
So because I find my Dash/Zeb ghost on rocks and/or stressed throughout the game, it too, rarely finds the opportunity to take an evade action.
Another problem occurs once the A-Wing goes down; there is no easy way to block/deny actions AND get a shot. Zeb crew helped with this, but that combo rarely, if ever kicked in against aces, Dash, scouts, etc. Two ghosts alone can't take down aces or other meta-heavy lists efficiently like 2 ghosts and an A-Wing can. Both myself and Davidhaus have found that losing the A-Wing early leads to an uphill battle and most likely, defeat, because of the reasons listed above.
Initial Problems-
The problem(s) I found with this list was that both ghosts were different pilot skills, so there were a few instances where they would be running close to one another, and unnecessary bumping occurred. Having differing PS ghosts disallowed the opportunity to choose between them which moves/shoots first. Second, I rarely ever remembered Chopper's ability because it either never occurred in a game, or when it did, it really had no effect whatsoever. Third, Zeb crew I found throughout my games hurt me more than it helped.
An important note here, if you have no docked shuttle or a R1 turret, a ship, touching the rear arc of a ghost with Zeb crew, can fire on the ghost without return fire. I never had to worry about this because I had the AB turret equipped to chopper. The next problem was the lack of AB turrets on both ghosts. Aces can eat a ghost alive 1v1, at least with the AB turret, I could stand a chance at doing damage. But with 4 attack primaries, damage output wasn't the problem, it was really only getting high agility ships within R1 or R2 in arc consistently.
First Revision-
With the problems listed above I revised the original list to this: https://geordanr.github.io/xwing/?f=Rebel%20Alliance&d=v4!s!158:36,120,-1,-1,160,97:-1:-1:;158:36,120,-1,-1,164,165:-1:-1:;32:72:-1:-1:&sn=Ghosts%20on%20Target%20Mk.%20II
With this new version of the list, I was able to move either ghost first as well as shoot with either one first. With movement, I have used the trick where if two same-PS ships are in line, the back one does a 1-straight, bumps and stays put, while the one in front is free to do whatever movement it was assigned. Similarly, the ship in the back can do a maneuver that barely clears the ship in front of it, and then the ship that was previously in front, is now in the back. It does a 1-straight and self-bumps. This technique is crucial if you have a ship being targeted and you don’t want it to be attacked this round. By having the ability to choose which ghost move first I can switch up the ships’ positions, and intentionally bump with a ghost I don’t want shot. But I still had Zeb crew, so by bumping in arc, I had no control over the fact that the ghost with Zeb crew could still be targeted. Again, through the next couple of tournaments, I finally realized that Zeb crew had to go in favor of another crew member.
Second Revision-
After ditching Zeb crew, I needed another crew member, but only four other options existed. Bombardier (1pt) was useless on the ghost, so it wasn’t considered. Next was Nien Numb (1pt), he basically made my 3- and 4-straight maneuvers green, which made the ghost a little faster coming out of a red maneuver. The problem I found though, was that I almost never needed a green 3- or 4- straight in any of my previous games. Sure it would’ve been nice, but there are some other crew upgrades that offer even more than that. Next is Chopper (0pt). This little droid is an auto-include for any list already at 100 points or those with less that don’t wish to spend any more points. I thought about adding him to my Dash crew ghost, but in order to use chopper, I have to be stressed AND I cannot be on a rock. Chopper was clearly situational, and I know that the situational/synergy lists usually don’t work out the way you want them to. The last crew available was Intelligence Agent (1pt). This guy/girl was the answer that I was looking for the past few tournaments! Intel Agent, looking back on when I used him, has helped tremendously in certain games, while in others, maybe not so much. Against aces and higher PS ships, I can see where one ship is going and take actions according to where it will be and where its firing arc is lined up. I can also know exactly which ghost I need moved first, in order to block or self-bump for advantageous positioning. https://geordanr.github.io/xwing/?f=Rebel%20Alliance&d=v4!s!158:36,120,-1,-1,40,97:-1:-1:;158:36,120,-1,-1,164,165:-1:-1:;32:72:-1:-1:&sn=Ghosts%20on%20Target%20Mk.%20III
Sometime later this week, I will write up a BatRep on the regional I attended this past weekend and how the list matched up against the crazy meta we now have! davidHaus also brought this list to the regional, but with his final twist: https://geordanr.github.io/xwing/?f=Rebel%20Alliance&d=v4!s!158:36,120,-1,-1,40,86:-1:-1:;158:36,120,-1,-1,164,165:-1:-1:;32:72:-1:-1:&sn=Ghosts%20on%20Target%20Mk.%20III%20v2
Edited by Franch