Alisaie is strong-willed, cynical and, at times, emotional. She is compassionate, concerned for a traumatized Koboldling that lost his parents, and leaving a bouquet of flowers in memory of her grandfather, Nael van Darnus, and Bahamut's children.

By her own admission, Alphinaud was always the more clever of the two while she is more direct. This distinction is most pronounced when she summons an aetherial blade to attack the Warriors of Darkness, rather than summoning a carbuncle like her brother. Unlike her brother, Alisaie had little interest in the affairs of the city-state's politics, tiring of their petty power struggles. She strikes out on her own while her brother joins the Scions of the Seventh Dawn, but upon reuniting she becomes more involved, especially with the missions against the Warriors of Darkness and to liberate Doma and Ala Mhigo.

Though Alisaie loathes politics, she has proven to be quite persuasive when negotiating, or at least when striking a deal. She has a humorous side, often teasing Alphinaud (in a similar vein to Krile) and making cynical comments. Although this seems like petty sibling rivalry, it shows that she knows and understands Alphinaud unlike anyone else. Alisaie resents being compared to her brother or being mistaken for a boy. She deeply cares for him as he does for her, and when Alphinaud goes missing during a diplomatic mission to Garlemald, Alisaie constantly worries for his whereabouts, even stating that should he die on her, she will never let him hear the end of it. From the latter parts of Stormblood through Shadowbringers, Alisaie becomes irritated by those around her and even defensive, angrily grabbing Alphinaud by his collar after jokes about seeing a bratty pixie as reminding him of his childhood, to sounding outright snappy when her idolism of the Warrior of Light is brought up in embarrassing context.

During her time in The First, Alisaie befriends Tesleen and Halric, two of the many light-corrupted patients at the Inn at Journey's Head who seek to live out their final days before becoming sin eaters in peace. It is implied that Alisaie's attachment to them and the other patients stems in part from her inability to help Ga Bu back in Eorzea. After witnessing Tesleen's transformation, Alisaie's determination to undo the Flood and aid the Warrior of Darkness in their struggle grows. If brought into Holminster Switch as part of a Trust, she will express sorrow at having to fight the corrupted Tesleen, wishing her peace after the battle.

Alisaie is the more pragmatic and direct of the two, most often concerned with the possible ramifications of a mission. Like Alphinaud, Alisaie greatly respects the Warrior of Light, and is especially grateful for their support during trying moments. She views the Scions' core members as close friends and cares greatly for their well-being.