You will need root permission to do that... If you want your wallpapers to be available in xperia wallpapers, copy them to system /etc/customisation /content/com/sonyericson/wallpaper picker...
I wrote that path from memory.. So just make sure it is there
thank me if I helped you...Don't say it,hit the button...
Sony Xperia E dual C1604
MY OWN NoZ ROM
STOCK KERNEL WITH CWM.....
HIT THE THANKS IF I HELPED YOU...IT'S FREE ACTUALLY BUT MEANS A LOT TO ME