Hi @Keerthi
You also need to override cart functionality beacuse every order is placed on basis of cart data, so when you add item in cart you also need to store your base image path there. So create column in cart_item table to store image there. For it you have to create own your cart facades as we created in Checkout package.
Now you need to override add cart fuctionality for which you need to create your own route & coontroller and when user clicks on Add to cart then this controller will be called and store image in cart_item table.
After doing all of this you need to ovveride checkout's save order functionality for which you can do the above process and when this controller called you can see this
$order = $this->orderRepository->create(Cart::prepareDataForOrder());
in OnepageController.php's saveOder function.
in this code, your Cart::prepareDataForOrder() function should be used which we override before.
Thanks