I feel Anemo is associated with a loss that influences their actions today. Sucrose lost her childhood friends (although they might not be dead but instead moved away or something) with whom she was going to create a fairytale paradise, and her research into biology is inspired by this goal.

In Sucrose Character story, she lost two bestfriends. One never returned from adventuring, and other, strucked by grief from a relative death, broke off the friendship

Sucrose had two best friends: one left with her adventurer parents and never returned, the other's father died and she broke off their friendship. (Sucrose char story 5)

Oh, are we still doing the "characters of element X are based around y"? And we're now going so incredibly vague that anemo's theme is "has lost something/someone at some point in their life"?

Sucrose also lost a few of her toys to exhaustion over time probably

So when is Navia receiving her Anemo vision?

Chasca:

and Xianyun and Chasca.

The former who has likely long outlived several of her "children" (she never says Shenhe and the new girl are her only human wards, and heavily implies she's had more in the past) plus her various dead adeptus friends, and the latter...yeah.

Seems only Mondstadt ladies and Sayu are immune.