I want to copy files from my bucket but only files/directories that not exist on local drive.
Is it possible?
I tried something like
gsutil -m rsync -n -r "MyBUCKET" "my_local_dir"
but something is wrong.
You should try using the recently-added -i flag, which ignores existing files on the destination. That flag was added in this commit and should be available as of gsutil v4.59.