@Alice-and-Jeff0 - I have addressed the registration issue with Airbnb CS (both US & China) by phone four weeks ago. Both essentially said I need to ask the host because the need to register with the local PSB varies from city to city. I asked four hosts in Shanghai if they could assist. All said they would and had their documents available. The one I booked with said she would meet me at the local PSB. She did not say "Oh Airbnb does it for them, therefore you do not have to go to the local PSB". There cooperation leads me to conclude that Airbnb's new feature of adding passport information does not mean guests are definitively and automatically registered as if one were checking into a hotel.
Many hosts in Beijing describe their listing with a "No foreigner guests accepted" which leads me to conclude the law is more strict in China's capital city. I asked four hosts who did not have this description if they can assist in the registration process. Two said "no". One said "no need to register, just tell passport control you are staying at the Hilton". One said "too much trouble" but she invited me anyway. I booked a hotel.
So the articles written about Airbnb complying with China registration law do not give me confidence that guest are really "registered". I wish Airbnb would put out a definitive statement on this subject.
FYI, hosts in Tokyo are required to get their "hosting registration application" completed with Japan Tourism Bureau by Nov 1 and provide this registration number to Airbnb. This number is added to the host's listing. Hosts not having this registration number will have their listing de-listed from Airbnb. And any confirmed reservation will be cancelled.
I have already noticed that there are substantially fewer listings for Tokyo now than there were 3 months ago.
I am not an experienced Airbnb guest. In fact I have yet to stay in an Airbnb host accommodation. However I look forward to my first in Shanghai.