If you are running more than one keosd with independent data directories, then yes, you must import private keys twice if you expect them to be available on all of your keosd instances. Running more than one keosd with the same data directory is strongly discouraged. You are likely to encounter unexpected results, including crashes. It is ordinarily unnecessary to run more than one keosd when using the HTTP-enabled version.
If you are running multiple instances of `nodeos`, it is only necessary to run `create account` on the nodes if they are independent. If the nodes are connected and synched, it is only necessary to run `create account` once. If you are able to run `create account` on multiple nodes without error, that is an indication that your nodes are not synchronized. If you intended them to be synchronized, you have an error in your network configuration.