Keep Coding

Is there any way to get latency from AWS/ApplicationELB namespace? I know it is available in the AWS/ELB namespace, but I need it for AWS/ApplicationELB, as this is what I use.

The latency metric on ELB is comparable to the TargetResponseTime metric on ALB.
ELB Latency definition: (source)
The total time elapsed, in seconds, from the time the load balancer
sent the request to a registered instance until the instance started
to send the response headers.
ALB TargetResponseTime definition: (source)
The time elapsed, in seconds, after the request leaves the load
balancer until a response from the target is received. This is
equivalent to the target_processing_time field in the access logs.
Further Reading
AWS Documentation - CloudWatch Metrics for Your Application Load Balancer