Honestly I don't think they'll go near any of this. A Harfoot society in one era, a Hobbit society later in a completely different one, there's no need for this story to go into anything at all relating to the links between the two and they would be crazy to do so.

If we take the Harfoots as precusrors to the shire hobbits in any way, uplifted or not, there's still some unfortunate implications in them losing their Irish accents as they become "civilised", but the way around that is to view this as a completely separate continuity from the movies, or that they're not precursors at all, this tribe never settled in the Shire but live somewhere else.