I want to say the following
Pretty women are not necessarily attractive, let alone ugly women.
in Japanese. My attempt is as follows.
不美人どころか、美人も魅力的だとは限らない。
Is it correct and natural?
I want to say the following
Pretty women are not necessarily attractive, let alone ugly women.
in Japanese. My attempt is as follows.
不美人どころか、美人も魅力的だとは限らない。
Is it correct and natural?
I would say,
美人であったとしても魅力的だとは限らない。[醜]{みにく}いならなおさらである。
I don't think the word 「不美人」 is commonly used. For 'Ugly', '[醜]{みにく}い' or 'ブス' in an informal context would be more natural.
My Japanese expression above sounds to conclude that 'An ugly person is not attractive.' If the conclusion you want to deliver is 'Being pretty is not enough to make oneself attractive.', then you would say
醜い人が魅力的ではないのは確かだが、美人だからといって魅力的だとは限らない。