Hello Tigntaz,

If you want it to sound like an authentic Chinese name, you have to use one character for Jade and one single character for Phoenix. If you want the name to be taken seriously,the only logical choice here would be 玉凤（鳯）, because the other options honestly don't sound like real names. The only thing is, it sounds like the name of a peasant from the countryside. A word to the wise on this, names that include 翡翠， 鳯，凰，花，or the like as it's kind of been overused in the past and present day Chinese may think it a bit 俗氣...

Best to check out another series of dialogues from this site titled, "The Northeasterner"

http://popupchinese.com/lessons/intermediate/the-northeasterner

http://popupchinese.com/lessons/advanced/the-northeasterner-part-ii

Actually, I miss the misadventures of old 王翠花.