Hey, @va_monic .
That’s a great question! Thanks for reaching out. I’m happy to provide you with some more information.
It’s definitely possible to display shipping rates from multiple carriers at one time. Before we begin, may I ask where your business is located? As well, are you hoping to show carrier-calculated rates to your customers at checkout, for both FedEx and UPS? Do you have your own carrier accounts that you’re hoping to use? This information will be very helpful in determining your next best steps.
For example, if you run your business in the United States, you can use Shopify Shipping to display UPS rates. You could also connect your FexEx Carrier account, by enabling third-party carrier calculated shipping. Then, at checkout, your customer would have the option to either select the UPS rates or the FedEx rates. Is that the outcome that you’re hoping for?
Looking forward to hearing back from you, so that we can continue to work on this together.