Composure lets you take a Focus Action, so as long as your failed action doesn't stress you, and you've not already performed a Focus action on that ship (and you're not under other action restrictions), you'll be able to perform the Focus action after the failure.

Perceptive Copilot says "After you perform a Focus action, gain 1 focus token".

Because that's all PC requires, it will indeed give you two focus tokens with the Composure Focus action.

What Composure bans is any followup actions, e.g. Darth Vader's ability, the TIE Interceptor Autothrusters ability, chained actions, and so forth. Perceptive Copilot isn't having you do more actions, it's just giving you more tokens, so it totally works with Composure.