Hello,
During our Italy trip next year, we're planning to stop for few hours at Pisa & Florence before moving forward. Is there a facility to store luggage on train station at any of these stations?
Yes there are.
https://www.stowyourbags.com/en/shop/pisa/
Two years ago, we stashed luggage at the Pisa train station while we visited the city. It’s at the far end of the station, and we stood in a long, slow line. They charged by the piece of luggage. Picking up our bags took almost as long, so allow plenty of time.
Thanks to both of you!