People were able to discover the endpoints for Fortnite, I believe the same can be achieved for Apex Legends.
(Fortnite endpoints: https://github.com/qlaffont/fortnite-api/blob/master/tools/endpoints.js)
When I use Wireshark and Fiddler 4 and open the game, I am able to find a few http requests for authentication, but not much else. I am not a very advanced user of those tools, so I might not know where to look.
What would you recommend ?