Looking at recent character evaluations, it seems performance in Anwonjalbu is more important than even if Mei performs well in Legacy.

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In Legacy, Mei certainly
gets a lot of attention, but
in Anwonjalbu,
she isn't quite as dominant,
so her character evaluation ranking is slipping a bit.
Still, since her performance
in Anwonjalbu
has been good lately,
I wonder if her next evaluation
will jump up significantly.