For those who are interested by the topic.
I started to found part of a solution
With the amazing magento You can give several permission to user accessing to the admin.
For this go in settings Permision Role and Add role.
Then you will see all your admin back offices functions with a checkbox next to them.
So you just check the sales statistics and users with those right will be able to acess only to this.
However they will acess to statistic of all the sales , it’s not possible to determine only the permission to some products.
But it’s already something that I discovered, which will be anyway great for my team…
So anyway if you know a module which give only permission to check sales of some specific products, keep me in touch,
Have a nice day,