Is there any difference between ～～をする and ～が～

Question

I came across this sentence (from the Core 1000 material of iknow) while learning vocabulary:

彼女は青い目をしています。 She has blue eyes.

Doing some searching I found this answer explaining that ～をする can mean 'to have some characteristic'.

Before that, I only knew of the following construction to express such:

～は～が～。 彼女は目が青いです。 She has blue eyes.

Is there any difference in meaning/implication between these two different structures? Or can I use them interchangeably in any circumstance?

Answer 1

They are almost the same. However, when they mean that her eyes happen to be unusually blue in the moment, the latter 目が青い is more likely to be used.