1) Yes. F pax could bring 1 guest.
2) I don't think so. I was in HKG in August and will be again in a few weeks, I did not experience too much inconvenience and do not expect in my next trip. I would not be worried about HKG disruption in Dec if I were you. If you decide to stay near HKG, there are a few hotels to choose from, but I would not call anywhere near the airport sightseeing tbh.