My Nana has gone by the name Joy almost her whole life born a different name. Joy suits her sooooo well I hope I am like her in the future. She is young at heart, loves to laugh and very motherly. Go for it.
What if your Joy is a cool, grumpy, scowly, grouchy, goth type though? A kid called Joy didn't invite my son to her party once and he was furious and said "hurrumph. I've never seen much Joy in her." They were around 7 irrc.
A very close friend of mine has Joy as a middle name and absolutely detests it?! Don't know why as it is lovely but she says it was always like being called 'Happy' but I guss it's no different to beig called Grace or similar? I like it fwiw
I was sat next to a Joy in the 'Overcoming Depression' course the doc sent me on for PND. Found it very hard to keep a straight face as she sat there with her name sticker on. Put me right off virtue names but did help cheer me up!
When she's in a sulk or pensive or angry there will always be some smartarse pointing out that she isn't exhibiting much joy.
There was a recent article in The Guardian by someone who called their daughter Merrily and she hates it and wants to be called Victoria instead.
"We liked the way it carried music with it, along with connotations of laughter and joy what was not to like? Merrily has told me since that it's those very associations with her name that have caused her the most irritation."