If you have the dev home app for xbox installed on your xbox it is possible to setup a Charles proxy to monitor the HTTP traffic.
Follow these steps to install the dev home:
https://www.windowscentral.com/how-activate-dev-mode-your-xbox-one-console
Once the dev home app is installed you can enable the device portal on your xbox:
https://learn.microsoft.com/en-us/windows/uwp/debug-test-perf/device-portal-xbox
This is where things get a little hacky, but your going to end up using Charles instead of Fiddler to monitor your devices traffic. You will need to install Fiddler to get a FiddlerRoot.cer (http://docs.telerik.com/fiddler/Configure-Fiddler/Tasks/FirefoxHTTPS), which you upload to your xbox through the network page in the xbox device portal. Then you simply enter your laptops IP address in the "Host IP address" field, and the Fiddler port is the port number defined in your Charles Proxy Settings.
Then you press the Enable button, which will prompt you to restart your xbox. Select the Restart button, and once your xbox restart you will begin to see HTTP traffic in Charles.