There is a low demand when it comes to .cx extension. If you look at sales, it's very low.
Since the keyword is Ethereum which is hot and trending, you might get lucky.
Put a mid-high xxx tag and wait.
You may very well be sitting on a goldmine. According to urbandictionary.com, .cx among other things is also a abbreviation for CryptoCurrency.
CXP.com sold for $31,000 at SEDO last month. (crypto price?)