Sounds fun. c: I guess I'll claim a spot!
This is actually a really good question! I picked both at the same time.
Both names are actually fairly recent (from maybe 2015? maybe a little earlier); he used to have a different real name and nickname. His original real name wasn't anything particular, and his nickname was "Anti" because he was, to his friends, seemingly against everything-- but I don't like the sound of it, and that word has other connotations now, so it was time for it to be replaced with something more fitting.
His original real name was Arabic (Muslim), but I wanted something Oromo (ethnically Ethiopian) instead, because a theme with him and his family is valuing their heritage vs. him trying to stake out his own identity, so they have traditional names and nicknames ("Didaa" is his family nickname, "obstinate"). I looked through Oromo name lists until I found something I liked, both in sound and meaning, and something that would suit a "punk" nickname. Izzy doesn't mind his real name, but he's young and kind of sick of his family's expectations (they're not bad to him and he loves them, but he's ready to stretch his wings) and he is trying to make his own identity for himself, from his clothes to his actions to his band to his name, and so he picked a "punk" (Western) nickname for himself that he wants to be called. From my standpoint I was thinking of something along the lines of Iggy Pop or Johnny Rotten, but I wanted something that didn't have a famous person already using it, so when I found Iskinder, I thought that worked perfectly as a full name for an Izzy-- and I think Izzy just suits him.
"Eba" means blessing or monkey, a monkey's cry, and he's the baby of the family; he is their blessing. He's also always been a loud and rowdy kid, lol
"Iskinder" isn't a surname, it's his dad's name because of Ethiopian naming conventions. It means "defender of mankind" which suits his dad and maybe it'll be something Izzy grows into, too...