It's almost been confirmed that NYCFC will have its own academy in New York City (or the surrounding area). There may be the odd player moving between academies as befits their potential, but they aren't just going to send all of the players to Manchester. Besides, it would make no sense to do so. MLS has specific rules protecting your "rights" over a player who has come through your academy - they get several years of exemption from selection in Expansion Drafts, for example - and you can bet that MLS would not recognise MCFC's academy as a NYCFC academy, so you would be throwing away your protection.