Indian sellers can sell products as a vendor on WarriorPlus if they Use 'PayPal Plus'.
What is PayPal Plus?
See this article to learn more about what PayPal Plus is, how to connect it to your W+ account and how you can use it as a vendor from India. (http://help.warriorplus.com/en/articles/3307929-what-is-paypal-plus)
Additionally, there are no restrictions for Indian affiliates.