from this page
https://www.ihg.com/content/gb/en/customer-care/travel-advisory
Hotels are subject to local law in the market in which they operate. Therefore, government legislation and regulations may supersede this policy in specific circumstances. (including the type and timing of the refund).
If Italian law says no refunds but a credit note then that's what you will get.
I'm not sure a chargeback would work as the hotel is following Italian law. And a charge back also relies on your credit card provider getting its money back from the hotel and if the hotel can't legally pay then the charge back will likely be declined or if inirially granted reversed.