Just throwing names out there as possible actors for the twins, though that might be too unknown to be worthwhile, but assuming they go with an actress or actresses of middle eastern descent who are older than their 20s, what about Sepideh Moafi? Maybe she's too big right now or having too much of a moment to be likely to take a supporting role like that, but maybe it depends on how big a role they make the twins.
I think it's always fun to speculate on it, anon, even though I agree that there's a good chance they'll go with relative unknowns (although they didn't for Gabi, Akasha or Marius!). Sepideh would be a super interesting choice - she really impressed me on The Pitt last season! - but I'm not sure what her commitments are to that show? Shabana's been able to star in another series though, so you'd hope there's space if she is a potential for the roles.
My dream casting at the moment is Zahra Amir Ebrahimi (everyone go watch Shayda and Holy Spider!), but she probably is too big for this show these days, as is May Calamawy, who I'd love and is actually of Palestinian descent too so could speak to that heritage and history in the characters. Sheila Vand could be a really cool choice too, as could Maia Abbass, who are both really unique and powerful actresses! I really like Helena Sawires too, but she's probably too young and every role I've seen her in is kind of too cute for me to imagine her as the twins, haha, but I'd love to see her given the chance with a role like them!