thats right, they're real name rearranged with an added x
1.
2. zigbar=braig, but in NA version it is bleig
3. xaldin=dilan, but in NA version it is dillin
4. vexen=even, evne, enev, enve, eenv, eevn, neev, neve, nvee, veen, vene, vnee
5. lexaeus=eleaus, but in NA version it is eleus
6. zexion=ienzo
7. saix= sai, sia, isa, ias, ais, asi
8. axel= ael, ale, ela, eal, lea, lae
9. demyx= demy, deym, dyme, dyem, dmey, dmye, medy, meyd, myde, myed, mdey, mdye, emyd, emdy, edmy, edym, eymd, eydm, ydem, ydme, ymed, ymde, yemd, yedm
13.
i would have also put up luxord, marluxia, and larxene except that they have the most letters and it would take and hour to type out all of their possible names