Hi yaima64721 it is not possible.Any way you can ask your friend or relatives whom you trust to do a paisapay payment to buy from ebay.You can send money to seller if you trust him.You cannot send money to ebay to be sent to the buyer.
If the Seller accepts payments other than PaisaPay, then you can pay the Seller directly. However, paying money to an unknown person can be risky. That is why eBay has their own payment gateway - PaisaPay.