I changed one of my old accounts from 2009 from geodude to firebunnymatrix I haven't lost trophies or my rank in fighting games .
check on psn go to friends then try search in the box try finding if theres names that got already taken or not?
Heres some name you can use I just thought of (been thinking hardcore lately since listening to both rap and metal with little added other stuff)
Wolfbane(whatever) example wolfbanehenry
wartaka ( I think taka is hawk in japanese?)
stranglehold(whatever) example: stranglehold_jack
red_akihaba (not akihabara with ra added)
solid_wolf(was thinking solid snake)
deadstormtyler (i tried deadstormhenry it was not as good)
shinhyaku(whatever) (hyaku means 100 in japanese)example: shinhyakumuerte (muerte means death in spanish)
I game on all consoles and PC