How do I (29M) tell my wife (30F) that I want a cuckold relationship?

We’ve been married for 2 years and been together for 4. We have a healthy sexual relationship although after the arrival of our kid we don’t have sex that much. The thing is that I want her to be more of a hotwife. To give you an example of my “dream” :

I would like it if we go for vacations and we stay in an adult only hotel where she would have the freedom to flirt with whoever she likes and she can have sex or just flirt with him for as long as we are there.

Do you have any advice on how to approach this? Should I just keep fantasizing about her with others or I should talk to her?