Open the lib/architecture/ folder and check if there are both libUnityARCore.so and libarpresto_api.so files. There seems to be a bug where a Unity export does not include all lib files. If they are missing, use Unity to build a standalone .apk of your AR project, unzip the resulting apk, and copy over the missing .lib files to the unityLibrary module.
However, during export there are no lib/architecture/ folder at all. There are .aar files only inside libs folder
Repeat steps 4 and 5 from the Android Platform specific setup (editing build.gradle and settings.gradle), replacing unityLibrary with arcore_client, unityandroidpermissions and UnityARCore.
doing step 8 literally, leads to build errors
Expected behavior
Actual instructions how to setup AR project
Describe the bug Setup AR section
However, during export there are no lib/architecture/ folder at all. There are .aar files only inside libs folder
doing step 8 literally, leads to build errors
Expected behavior Actual instructions how to setup AR project