There are several outlets in series. Two of the outlets have no power when you plug something into the outlet, however, the hot wire going into the back of the first outlet is live (has power). When a tester is used, the tester indicates hot/neutral reverse. Before I make another trip, does this sound like the outlets are bad?
According to the tester, at least one of the outlets is not wired properly. IMO it is not your job to determine whether an outlet is bad, but simply report if your tester indicates it is not providing power or if it is wired improperly. Diagnosis is the job of a licensed electrician.
If your using a simple 3 lite tester you can get a deceptive reading. I recently installes a Leviton smart outlet in a room for my wife. When I tested the smart outlet was hot but the outlet next to it (last in the chain) showed the same thing you stated in your post. I pulled out my meter and opened the outlets. In actuality, the hot multiple at the smart switch was open. Fixed the hot and all was well. Unless you are going to repair the outlet (way beyond scope of your inspection) I agree with Larry and James, report defect and move on. If your trying to learn, the best thing to do is study or build a teat circuit and see the effects. Fact is the simple 3 light testers do not tell you everything.