house cusp sign vs planet sign (+ NN question)


I just had a thought!!
Is there a difference in expression of a planet if it's sign is different from the sign of the house?

For example: Ascendant in Aries with Sun in Taurus in the 1st house. The 1st house is in Aries and the Sun is in it, but the Sun is also Taurus. Would the Sun have any Aries influences because of the ASC?

The specific reason why I'm wondering is because of my mom's NN. She has it in the 5th house in Aries, but her 5th house is in Pisces. I've been telling her that she should focus on her hobbies and pleasures in a simple, forward and unabashed way. But could it be that she actually has to do it in a Pisces way to get to her Aries NN?
Could it be similar to how interceptions work (getting to intercepted sign through sign on house cusp)??