I would look at the 1e FR boxed set, as she apparently started out as CG there. For that, it's probably helpful to note that FR was designed/introduced in the post-initial 1e/early 2e time where CG seemed to be considered the optimal 'good guy' alignment*. Unearthed Arcana through The Complete Book of Elves reinforced the notions of elves as CG as well, and I've always found the justification for that somewhat forced. My gut instinct is that Greenwood saw the goddess of beauty as 'one of the good guys' and slotted her at CG because that was the Good in vogue at the time. That, or maybe she is supposed to represent people's (gamers starting in the 80's) post-hippy free-spirit aunt.
*Lolth and Shar notwithstanding, there seems to be a strong trend to code female deities, particularly those that present as young adult women, as good figures.