Hi, Abishkek.
If we give permission to sellers to upload their products themselves, and if the product is already uploaded by a seller before, then since the seller cannot access products of others from the backoffice, he will not recognize that the same product has been already uploaded and he will upload the same product as a new one.
Only the shop owner with super user priviliges can see all the products, so it is okay for the shop owner. But it is not possible to moderate overall process. So I think it will be better if sellers can see all the products so that they can check if the product already exits.