Rosa is somewhat dated, you'd be unlikely to meet one under 45, it would be considered boring and dated, but it used to be quite common, especially in working-class environments.
Rosanna is not very common (but not odd either) and while it doesn't feel like a particularly "young" name, I can picture it on someone in her twenties or younger.
Luisa is always spelled this way, since Italian is phonetical and normally each vowel is pronounced individually. It feels more like an older woman's name, but there was one in high school with me, and I know someone who has a 5-year old girl by this name (they were likely named after a grandmother). These 3 names feel quite standard.
Siena is just a city in Tuscany, it's never used as a given name and would be considered weird and tacky. We don't really have "place names".