What is the ruling on selling via "dropshipping" and "e-commerce" given the absence of possession of the merchandise and the concealment of this fact, and what is the method to make this sale permissible?

It is permissible for you to act as an agent for the buyer for a known fee, provided that you are trustworthy regarding the price and shipping costs, and that the commission is specified. It is also permissible for you to enter into an agency agreement with the supplier to sell his goods and receive a commission on the sale. Furthermore, it is permissible for the transaction with customers to be merely a promise to purchase, where you display the goods and agree on a price, then you buy them and sell them to the customer. Finally, it is permissible to sell a described commodity in trust, to be delivered at a known future date, with its price paid upon contract.