Noise will definitely be transmitted, but unless there is shared ductwork that provides a direct conduit, neither party should be able to hear the other's conversation. Before you buy, have one person stand in the room upstairs and another downstairs. Walk around and talk to yourself in a normal tone and then you'll know how much sound carries.

Thank you for the suggestion!

Yes, I believe it is not appropriate to combine this guest room and its bedroom because there will be no privacy, so it would be better if they were separated by a small distance.

They are separated by a whole floor Get a good thick rug for the master no issue with privacy unless you get really carried away .I agree test it .