There is one thing I do not get about olden day women use to look like or a queen would look like or grace. It's people who are romanticizing or visualizing that women in those era were beauty (which by the way might be different POV what beauty was for them in those days, which we do not know). So according to this forum there are no possibilities of queen's to be plain looking.
To me yes any actress can play in period drama even women like Alia who might not be beauty queen can still play a character based in the past era. Like she pulled it off in Gangubai, her best performance till date.
So no we do not need only Aishwariya Rai or DP to play queen roles.
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