I'd go with
Anna. I love
Lily (obviously) but
Lily is in the top 20 now and when you add the popularity of
Lillian,
Liliana (which makes the top 100 when you count all spellings),
Lilia (makes the top 1000),
Lilith (makes the top 1000) and the various spellings of
Lily that are popular as well (especially
Lilly) the name is way too overused. I think most girls who are named
Lillian,
Liliana,
Lilith etc go by
Lily at least sometimes. It is possibly the most popular name of all, if you add all variants and consider all the girls who have a longer form but go by
Lily.
I like
Emilia, but it is easily confused with
Amelia which is also common. I think she'd have a lot of 'No, not
Amelia E-M-I-L-I-A.' situations. It's lovely, though.
I dislike the meaning of
Leah and find the sound insubstantial.
Julia is very 80s dated to me. I was born in the late 80s and know tons.
Liliana is fine, but doesn't excite me.
While I do think
Anna is also slightly 80s dated (I grew up with quite a few) it isn't very popular anymore and its popularity seems to be going down. Also it is easy to spell and pronounce.
1.
Anna2.
Lily3.
Emilia4.
Liliana (I'd call her
Lily)
5.
Julia (if I had to use it, I'd call her
Julie)
6.
Leah (I think I'd call her
Lee)
If you love both
Lily and
Anna so much, have you considered Lilyanna (I think it looks sweeter than
Liliana). Or maybe you should just go with
Liliana because you get your favorite names, and two other favorites as nicknames. It might be the ideal solutions.
Liliana Emilia is really nice.