Great question — answering as the UphillTech team:
Navigate to wp-admin->Dokan->Settings->Selling Options->Then select "Pending Review" for the "New Product Status" option. It will pending the seller products instead of publishing directly. However, if you want to allow to publish directly for individual seller then navigate to wp-admin->User->edit specific seller profile->then enable the 'Publishing' option.
Full answer by Mahbubur Rahman: https://stackoverflow.stackexchange.com/a/38710965 (CC BY-SA 3.0).
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