Ryan is masculine no matter which way you spell or misspell it.
This. You are naming your girl a boy's name, which is fine because it's your baby to name, but you have to own the fact that doing so incurs some additional complications. For example, people might think your daughter is a boy, or people will misspell her name, or people will strongly dislike her name. If you are not up for this, choose a girl name.
For the record, I do not prefer boy names on girls.
Also, I initially thought Rian would be REE ON.