I'm a brave charismatic Iranian,
And a cheeky Egyptian rogue,
And a small mongrel amphibian,
And a serene nameless lake,
I'm all twelve of these things but only one at a time,
Despite what you may have heard, I'm not related to whales or dolphins,
Who / what am I?
I would categorize the clues as follows:
Clues that lead you to the answer: charismatic Iranian cheeky mongrel
Clues that corroborate the answer: Egyptian rogue amphibian nameless whale
Clues that not everyone will know: brave small serene lake
95% chance you will learn something new from this riddle: dolphin
The riddle points to homonym for certain clues, but use other tags from Hint 1 too.
(I modified hints 2 and 3 so you might want to recheck them).
If you know what this is, you should be able to solve the riddle. It might leave you feeling sheepish.