Trump wins in the long run even if he loses this round.
It is conceivable that some court could enforce the old notice and publication and due process requirements routine whereby a party needs to have had reasonable and documented notice of what the the rules of the road were before being sanctioned for a violation.
That would be awesome though. Acosta can't follow any reasonable rules so that would all accrue to the President's favor over time. A rule requiring participating "journalists" to discontinue questioning and yield the mike when the President or Press Officer has clearly recognized another participant and asked the previous one to stand down, is not a rule that the court will disallow- only that they might- note "might"- require that it be documented and made known. Acosta violates that frigging rule five times a day. That would work against him.
Trump doesn't help though because he likes to rumble. Other presidents and press secretaries have handled this by just not calling on people who have been bad and freezing them out, and that will always remain an option even if Acosta wins some temporary relief, unless you think the courts are going to get into the business of telling presidents who they have to recognize at press conferences. Ahhh..I don't think so.