This should already be available. Nicehash Ethereum and Nicehash HNS pools are available. NbMiner is an example of mining software that can dual mine these.

If you manually setup your Managed Miner, you will have to create a Pool Group (Options dialog, Pools section) where you include Nicehash Ethereum and HNS. In the properties of your Managed Miner you select NbMiner as software, select Dual Mining for Ethereum + Handshake and finally select the Pool Group you just created.