What if Xerxes, King of Kings of Persia is really a bald man who wears a lot of golden bling while being almost naked all the time? Just like what he is depicted in 300?
No this is not ASB, there is no magic, no significant alternations to Persian cultures and soldiers, and definitely no other 300 elements getting into. It was just Xerxes' personal Fashion Statement, and the Achaemenid Aristocrats and Military under him just basically said a collective "Ehhh?" shook their heads, but let their King of Kings having his own bold Fashion Statement.
And yes, ITTL, we knew this because King Xerxes in all accounts about him (Persian, Greeks, etc) is always being noted as a scantily clad bald man with a lot of things, even and especially in relief and paintings, but he also oversaw the somewhat successful Military Campaigns as well as the Building projects his OTL self has also done.
Bonus points if some future Persian Kings adopt his fashion statement as well, not always being boring long bearded long haired guys.
So there will be two versions of "acceptable" Persian Noble style, one is standard like OTL, and the other wearing speedo and brings.
Add: This is not ASB, Kings and Emperors have gotten away with worse in Antiquity and Medieval Period, lets assume aside of the weird fashion, Xerxes stayed just as competent as his OTL self.