"Do you know where Egypt is?"
Translation:Apakah kamu tahu di mana Mesir itu?
What role does the “itu” perform here?
"itu" can be omitted here.
It has no specific role in this sentence.
It's sometimes used like that in everyday speech, and the position can be switched, like this:
"Kamu tahu Mesir (itu) di mana ?"
"Kamu tahu di mana (itu) Mesir ?"
"Kamu tahu di mana Mesir (itu) ?"
When used like this, and it appears in the middle of the sentence, it feels like the sentence is broken in two.
In all these sentences, it's optional.
Would "Kamu tahu di mana Mesir?" work? Or "Kamu tahu Mesir di mana?" maybe?
Yes, both are okay.