I freaking love the letter X. Getting the chance to use a word or name starting in X is like finding a needle in a haystack, so why not seize the opportunity as much as possible?
Xylona is a Greek name derived from the word xylon, meaning “wood” or “woods.” The name itself possibly means “from the woods/forest.” It appears to be a more modern creation, though based in sound etymology and not just created out of thin air. Related names include Xylia and Xylina, with the nickname Xylie. I have a character named Xylona.
Ximun is the Basque form of Ximeno/Jimeno, a Medieval Spanish name which is either a form of Simon or derived from the Basque word seme, “son.” The feminine forms are Ximuna, Jimena, and Ximena. El Cid’s wife was named Ximena. Though Jimen/Jimena is the most common spelling today, the X spelling is the original, and still used by some people.