Well, England did not control all of Ireland at this time, which means that the parts that France is able to exert effective control over will be limited to the eastern Pale around Dublin. This does not mean that the French will not be able to expand their control over the rest of the island, of course, but it will take time. My gut feeling is that France may advance a more 'hands-off' policy than England the same time, France will know that an effective presence in Ireland would also be useful to flanking England (and, coupled with the Auld Alliance with Scotland, they effectively have the English surrounded). Because of this, I suspect that they might be more conciliatory towards the Gaelic Lords in the West, whose support they would need to maintain order throughout Ireland. This, of course, butterflies away the rebellion and the Flight of the Earls.
Now, of course, Ireland is going to be viewed as a dagger pointing straight into the heart of England by the English rulers and I could definitely see efforts to conquer it; especially once the Protestant Reformation heats up even more, and England suddenly realizes that it is surrounded by a hostile Catholic power.