I pulled out my Rex Bills book ‘The Rulership Book’ out of curiosity.  Venus rules dimples.  I cross referenced by sign and planets and, again,only Venus was mentioned.  So, I would imagine that either Taurus or Libra rising could be in play but also Venus in the first house or in aspect to theAscendant.  But it’s pretty hard to pin down someone’s look by he ascendant alone.

FYi freckles are ruled by Mars.

I have dimples. I'm Cancer Sun and Scorpio ASC. My mum had dimples, she was Sag Sun and Leo ASC, and my grandad had dimples too, he was Aries Sun, ASC unknown, but as I do have Moon in Leo, he had it too. I don't think there is a rule

My niece (Pisces rising with Neptune in Pisces, 1st house) has beautiful dimples!

Also, I got a dimple in my left cheek when my Ascendant progressed to Libra.

I have dimples and consider it a Jupiter thing... but this thread is interesting. Maybe I'm wrong about this.