Both are part of Encryptotel and are hosted on two different blockchains.You cant swap between both and this is currently being worked out.
So eventually we will be able to swap the ETH token to the WAVES token, and the other way round? Has there been any ETA given when this will be possible?
I don't think this will happen in near future because at the moment no tool ready to do this swap. It was planned before the ICO but nobody working on it maybe the team will buyback all Waves token and burn that in coming days like they did in past.
They share the experiences between other projects like Primalbase and MobileGO. Hope eventually we'll see good swap technology.