On further investigation this looks like a path handling issue on the windows version. If I run the command with full paths from my user home folder it works.
I’m running docker for Windows desktop with k8s enabled locally. I also have AKS cluster. This isn’t related the the k8s config in use.
Also, the executables in the bin folder of the zip file for Windows do not have file extensions, thus windows doesn’t recognize them as executables until they are renamed appropriately.
I was having the same issue and I am in a similar setup as you did (windows 10, docker for desktop and k8s is enabled from docker).
I found a work around - since it complain cannot find .kube/config, the word around is to put the couchbase-cluster.yaml file into the home folder which helps cbopctl to find the k8s config file.
Hope this helps.