https://github.com/ThomasHabets/tlscheck
This is not an official Google product.
$ go build tlscheck.go
$ cat > endpoints.txt
# Simple connect to load balancer.
www.bing.com:443
# Connect to a specific backend and use SNI for real host.
www.bing.com/a-0001.a-msedge.net:443
^D
$ ./tlscheck < endpoints.txt
[… any warnings or errors …]