If the whole product line shares some personas, and a design team goes to visit some of those personas in the wild - it would be extremely helpful if they could drop the things they learn about personas in share it across the product line
Thank you for your request. It is currently possible to add products at the product line level. To do this, select the product line in the main navigation and then go to Strategy > Personas.
When you do so, these will show up at the product level as inherited personas (see screenshot.)