Using label_values together with the __name__ label and a top level variable

Hi,

I’m using the __name__ label in order to collect a variable from two metrics.

e.g.
label_values({__name__=~"node_disk_reads_completed_total|aws_rds_disk_queue_depth_average"}, node_name)

Is it possible to add into the formula checking for a top level variable too?
Here is a formula that isn’t working.
e.g.
label_values({__name__=~"node_disk_reads_completed_total{region=~\"$region\"}|aws_rds_disk_queue_depth_average{region=~\"$region\"}"}, node_name)