Noise machine vs fan?

I’ve never really considered getting a white noise machine because we always used a fan with DS (dear son) and also in our room so I kno shes used to it. But in her room it’s a diff fan/noise than the one in our room. It’s an oreck air purifier. My son has one in his room too he’s 7 and has used it since day one of his life.

Just kinda wondering if I should switch the fan that’s in our room that she’s used to into her room (in process of transitioning to her own room - this will be night 3. She sleeps in there first half of night and then I bring her to bed w me which I need to stop doing. I’m just lazy and most of the time it’s just me doing night duties) or maybe consider a noise machine. I don’t kno how necessary it is since my first never had issues..

Question is what do y’all use? Do I need to go out and buy one or is a fan just fine in your opinions?

Thanks!!!!