What do you mean? The Italian male name Andrea and the English female name Andrea aren't unrelated names that happen to be spelled the same way. They are one and the same name, both derived from the Greek word for "man"; the Italian name has managed to remember that it's overtly masculine and the English name has forgotten this.
-elle is pretty clearly descended from one of the usual Latin diminutives (also visible in e.g. Spanish tortilla). -ette seems to come from a much rarer one?
There's a fun map on Spanish wikipedia of which diminutive forms are preferred in which parts of Spain: https://es.wikipedia.org/wiki/Archivo:Diminutivos_del_espa%C...
Yes, both are used commonly. In names, there are Gabrielle, Cyrielle, Annabelle, Axelle, and many others. I am not sure there is any rule.
https://en.wikipedia.org/wiki/Gabrielle_(given_name)
Another commenter believes, in Romance languages, that the "-a" feminine gendered suffix is diminutive compared to "-o" masculine or neuter suffixes, but that is not true. Not for Latin, or Spanish or Italian or even Greek.
They are directly derived from the feminine Greek word "andreia", meaning "courage" or "virility", which had been derived from "andros", as supposedly a quality typical for males.
That's not really what I said. The name is a masculine name. You can name your son "virility" without problems. If you try to do that to your daughter, you're going to have problems. The grammatical gender of the word is a separate concern.
Andrea as a female name is similar to Carla or Caroline. Take a name that means something related to men (but no longer obviously so) and adjust it a bit to make it a female name. As a male name it just reflects changes in pronunciation over time.
Also, fun fact, I got invited to a ton Women in Tech stuff. I even got recruited to a company that was proud of having > 50% women in their teams. I assume that was because I was working on an OSS project (Chromium) and I had no avatar there.
Also, in the two FAANG companies I worked at I was added to women groups a few times.
I wouldn’t be surprise to meet a (female) Daniele. The second L is already dropped somewhat regularly in Michelle. Which is interesting because it came from the French, but since then the French spelling drifted to "Michèle" (and then more or less fell completely out of fashion, and then seemed to come back for a while). In any case, both are pronounced exactly the same way.
Michele and Daniele look like misspellings of Michelle and Danielle though. I don't know any women named Daniele or men named Danielle.