What would be such specific actions? Would a fed be intra-server or inter-server?
I don't know if in-game federations would be relevant in MC2, because a server is already like a Commonwealth (maybe even completely shared resources), so you players join a fed independently of their server? Or would the entire server join a fed? As the servers are decentralized, the latter would be rather hard to do.
The analogy we could make is:
|MC 1||MC 2|
|Commonwealth||Planet (one whole server)|
|In-game Federation||Community-made (not in game) cross-server trade agreements|