I don't know of any other full sized EC keyboards that support wireless, but depending on if they meet your needs, I know that Varmilo makes selfcontained EC switches that are hotswap compatible with Cherry MX switches. They aren't going to feel just like a Topre dome used in a Realforce since they are quite different in construction, but they are electro-capactive. If you don't need a full sized keyboard, you may have more options via Topre clones like some of the NiZ/Plum/Royal Kludge keyboards.

Look into Niz keyboards, and keyboards from other companies that use their switches.

Not an answer, but didn't some manufacturer recently make a capacitive switch in an MX format?