Oh OP I feel your pain. My DD2 is a similar age and still to this day I have a simmering regret about her name.
I think you should do what you need to do.
I wanted Rowan but my husband said absolutely no more R names (firstborn has an R name and my name also begins with an R). Which I really wish I had pushed on since I would be so happy now if she was called that. I get it would be confusing tho. Plus FIL and one of the cousins is called an R name so I get there are already a fair few in the extended family. My second choice was Elliot (so I obviously love your name choice ☺️) which we could have shortened to Ellie for a girl, but my husband was a big no on that again since it really is a boys name. But again, wish I’d pushed. I love androgynous names that aren’t common, and I think this is my issue wirh my DD2s name (as it’s not androgynous, tho it is uncommon so it doesn’t get the full satisfaction-tick-in-the-boxes).
In the end we settled on my third choice. This kinda adds to my guilt now cos it was still my choice but I dislike it now. I just got obsessed with having a nature ref but it’s pretty tenuous nature ref and I wish I’d researched more androgynous-leaning-girl names and forgot the nature ref. (Willow would have been better than this one! -my fourth choice, although not androgynous so maybe not, unless we called her Will).
We tie ourselves in knots don’t we!
In conclusion to my situation my DD is dead proud of her name letter, says it’s hers. She is protective over her name so I’m leaving her to it. Not saying you should, I’m just telling my story as it helps me. The only thing that helped me feel more at ease is that I made up a nickname for her which I call her (added pip to end of her name and also call her Pipsy sometimes but she sometimes corrects me with her real name) and when I say this I feel happy so I’m leaning into this.
My uncle is called Matt but later found out it’s his middle name. Turns out he hated being called David. So he would have made that change at somepoint. I hated my name at aged 15 as it was usual, and for a while I asked people to call me Emma, but it didn’t stick. Now my name seems to be everywhere -which is the wrong way around 😂.
I def think if you find yourself reacting to the name you don’t like and you have a chance to change it do it. It’s ruining your quality of life otherwise. We influence our kids in so many ways, conscious and unconscious, when you change it this will be one of the conscious ways. If you are happy your kids will be happy.
There are no rules to life, and there is nothing to stop you living your life how you want (-and I include mumsnet judgement in this 😬, hopefully those comments just helped you keep your resolve).