Solved
EasyAntiCheat missing dll
EasyAntiCheat is missing the "EasyAntiCheat_x86" dll file. I've uninstalled and reinstalled Apex Legends, and have run the EasyAntiCheat setup application with no luck. I have the x64 version of the file, but am unable to download/find the x86 version.
Fixed this by going into the origin client and re-verifying the game's files. I feel very stupid now.
