Hello,
The brand system is related to the HikaShop core.
You have to create the brands, which are stored in the database like categories.
So it's an ID which is stored for the product brand.
In HikaMarket I can't change the HikaShop core ; so I cannot let vendors create brands since it will create a brand for the entire store and you can't have a control on what the vendor will do (make a typo, want to rename another brand, etc).
Depending your product verification workflow, you can create a custom field instead if you want the vendor enter some text every time.
Afterwards, you can, in your workflow, create or assign the corresponding brand for the fields that your vendor completed.
Regards,