Well a list: MO Knight Commander - just pretend to be a Crosier and you'll be fine. It's probably the best thing to pretend to be anyway. ISS Taowu - Is not a Celestial Guard so pretty much forced to pretend to be a Dakini, Deva or Crane. ISS Sforza - Is a Bounty Hunter. Masking as one of the Bounty Hunters makes this easy, but mixing in elsewhere is also pretty trivial due to the big mixed pile that is a Zhian Haris. WBA Tian Gou - Most of WBA's Fireteams are fairly trivial to get fully coherent so care need to be taken to mask as something that's not got a good tag. Skipping Haqqis JCT Sforza - Is a Bounty Hunter and Wildcard. Tunguska likes making coherent teams easy, which would make this difficult if the Bounty Hunter tag Sforza has didn't provide a hint to good units to pretend to be. OSS Sforza - Is a Bounty Hunter and can only link with Bounty Hunters. Easy peasy. Just don't pretend to be one of the wildcards. Tohaa Taagma - Just don't pretend to be the same thing as everyone else in the fireteam. Starmada Tian Gou - Same deal as in WBA. Many of your options can be a trap to reveal info you're there. Starmada Cho - You're Security. You can only link with Security. Just pretend to be Security. Easy peasy. Spiral Taagma - You're a brawler. That's a big hint. Pretty easy to get this right. Dahshat Sforza - Isn't a Bounty Hunter for once. Sectorial is in general pretty difficult to make coherent if you mix teams so this should be easy for Sforza to blend in. WhiteCo Taowu - Much like Dahshat, WhiteCo almost immediately breaks cohesion when they mix so it should be easy to blend in here. -- So to sum it up most Holomaskers are easy to get to blend in. There's a few exceptions where it is hard (as in requires some real thought); ISS Taowu, WBA Tian Gou, and Starmada Tian Gou. Some requires conscious effort to self-sabotage such as Taagma or Knight Commander.
As of the current FAQ document: When are a Fireteam’s Composition Bonuses checked? A Fireteam’s Composition Bonuses are Private Information until the Resolution step of an Order in which their player declares BS Attack or Discover, when the MODs of the Rolls are determined.
One small question I have is if the Fireteam is Zhanshi Paramedic, Zhanshi HMG and Tian Gou; if the HMG shoots, will the lack of +3 to Discover remain secret?
This last part sounds to me like it is not treated as a special Rule (like "Discover (+3)" ), but more like a MOD you apply in the moment of using it, like range, Cover, poor visibility and so on. I think thats a good way to explain it actually thats not very sneaky, because Sforza does not roll for booty like all his scavenging pals, so as the only Cybermasked unit in this linkteam he reveals himself just after deployment.
