This has likely been discussed already, but I'd like the answer too. Chatting with my friend yesterday, we came upon a question neither of us could give a concrete answer to. He mentioned two situations where parts of the community had given him conflicting answers. In Onyx Contact Force, you can make the special Samaritan Haris with two Xeodrons. Nourkias "counts as" a Samaritan for the purpose of composing fireteams but my friend was told that he could not make that team since none of the models in the fireteam had the Haris rule to gather around. In the NeoTerran Capitaline Army there is the Fusilier link with CSU's who "counts as" Fusiliers for the purpose of composing fireteams. This time he was told that one could make a team of an Aquila FTO and two CSU's even though none had the Fireteam skill since the way "counts as" is described, you should be able to compose a fireteam around them. I argue for the former, but couldn't say so with authority.
There is no skill called "Fireteam: Core" so there are no need for any unit in the Fireteam to have a skill called that. There is a need for the Fireteam: Haris skill because the skill and the Fireteam specifies that this skill is required to be present in the Fireteam. Thus: Nourikas and two Xeodrons are missing the Fireteam: Haris skill and can't be formed. Aquila and two CSU have no need for the any skill because they are forming a Fireteam: Core.
