Ciao @Kris56 , as required by the Police department (Questura) in Italy you need to show your documents at check-in. You are not obliged to submit the documents in advance. The host has 24 hours from your arrival to send your ID data to the Questura.
But you could agree to send your ID data (not the picture of your passports): name(s) as on the document, surname, date and place of birth, nationality, sex, kind of document, number of document and place of issue and residence and the host can verify your data at arrival with your documents. It would make the check-in process easier, without stress and paperwork for the host.
Airbnb doesn’t give any information about you identity to the host.