Take Stuart's suggestion

script/configs/exclude_all_packages_app.yaml

@@ -5,7 +5,16 @@
 # An example use case for this list would be to temporarily add packages while
 # updating multiple packages for a breaking change in a common dependency in
 # cases where using a relaxed version constraint isn't possible.
-- camera_android_camerax
+
+# An application cannot depend directly on multiple federated implementations
+# of the same plugin for the same platform, which means the app cannot
+# directly depend on both camera_android and camera_android_androidx.
+# Since camera_android is endorsed, it will be included transitively
+# already, so exclude it from the direct dependency list to allow including
+# camera_android_androidx to ensure that they don't conflict at build time
+# (if they did, it would be impossible to use camera_android_androidx while
+# camera_android is endorsed).
+- camera_android
 
 # This is a permament entry, as it should never be a direct app dependency.
 - plugin_platform_interface