I have an App Engine app in asia-northeast1, but i could not specify the region for pubsub trigger.
This works:
functions.region(\"asia-northeast1\").htt
Same issue here: I've resolved setting Google Cloud Platform (GCP) resource location in Firebase Project settings, which was undefined, to eur3 (europe-west) (my AppEngine resources are in europe-west1)
Google Cloud Platform (GCP) resource location
eur3 (europe-west)
europe-west1