I’ve always loved the name [name]Annabel[/name] and even with its recent surge in popularity, it’s still on my list of names to consider. If I ever use it I envision calling the little one “[name]Annie[/name]”- maybe she’ll carry the nickname beyond just her cutesy years, that’ll be up to her. Whatever the case though, I don’t want her to BECOME [name]Annie[/name]. I’d want to still use [name]Annabel[/name] and for people to always know that’s her name. [name]Do[/name] you think this is possible? I’m a [name]Katelyn[/name] who went [name]Katie[/name] and never went back (and that’s fine with me) but I’d hate to see [name]Annabel[/name] get left in the weeds!
I feel your pain! On the very top of my list is [name]Isabelle[/name], and I love [name]Bella[/name] or [name]Belle[/name] for when she’s younger, [name]Bella[/name]'s cute, no matter how trendy it is. But I don’t want her to be [name]Bella[/name] when she’s 12, not to mention 22. [name]Isabelle[/name], to me, is stunning and captivating and charming, I want her to be [name]Isabelle[/name], not just [name]Bella[/name]. And I’m a big fan of nicknames, so I’m afraid if I start with a nn, I’ll keep going with it until the end of time. 
My little sister is [name]Natalie[/name], I call her [name]Tallie[/name], I’m the only one that calls her [name]Tallie[/name], and I rarely call her [name]Natalie[/name] anymore. And my other sister is [name]Rebecca[/name], but she doesn’t even want to be known as [name]Rebecca[/name], she feels like [name]Rebecca[/name] is who she is to strangers. If you know her, if you love her, you’ll call her [name]Becca[/name]. [name]Rebecca[/name]'s too formal for family. I call her [name]Rebecca[/name] sometimes because I think it’s so beautiful, because I don’t want her to lose that she’s not just [name]Becca[/name], she’s [name]Rebecca[/name] too, but I guess she doesn’t see it the same way.
I’m thinking I’d try and call her [name]Bella[/name] and [name]Isabelle[/name] almost equally–[name]Isabelle[/name] is not just for when she’s in trouble, or for strangers that don’t know that [name]Bella[/name] means she’s loved. [name]Isabelle[/name] is because it’s who she is and because it’s gorgeous. Maybe that would work for you, too? I feel like I don’t have much experience with it, since I never really had a nn.
I hope that’s how it is for all my children, though–they’ll have the nn from Mommy (because all my siblings had nns, I sort of felt left out), but they’ll also have the gorgeous full name. I want them to have both.
Then just call her [name]Annabel[/name] primarily and use nicknames sparingly. That’s what I did my ODD, [name]Isabella[/name]. I call her [name]Isabella[/name] 60% of the time with [name]Belle[/name], [name]Bella[/name] and Bells the rest of the time. Honestly, I mostly use her nickname when we’re alone too. Like if we’re in a hurry. Recently, she told me she likes [name]Izzy[/name] better. So sometimes the nicknames will only stick around until they’re old enough to figure out what they like to be called.
I don’t have much experience with this either, but I think if you introduce her to people as [name]Annabel[/name] and use both names regularly, she’ll become accustomed to both names. I know a little girl named [name]Elizabeth[/name], who, at home goes almost entirely as [name]Beth[/name] but when I helped out in her first grade classroom all of the students and teachers called her solely [name]Elizabeth[/name]. It seems that teachers these days are more apt to use full names, so she’ll likely be known as [name]Annabel[/name] by her peers.
However, I do agree with bellababy that there obviously comes a point where kids can pick nicknames for themselves. My friend [name]Nicole[/name] is [name]Nicole[/name] to acquaintances, [name]Nikki[/name] to friends, and [name]Coley[/name] to her family.
I would primarily use [name]Annabel[/name] and introduce her as such.
Whatever you do, don’t only use [name]Annabel[/name] when she’s in trouble or has done something wrong. That will condition her to hate the name as she will associate it with trouble and a lecture.
Spelling [name]Annabel[/name] the way you do will also limit the [name]Belle[/name] use as it won’t feel as natural as she ages.