According to the leaks, Mimi is Hydro Catalyst user from Inazuma region. We don't know any more about her yet though.
Here are 3D models leaked by Lumie. Check the original tweet here.
Lumie
@lumie_lumie
image
Matangkad
@Woohyunyeah
@NEPTUNE_XVIII Hutao ans rosaria is the next one according to leaks
DevilTakoyaki
@deviltakoyaki
(2/2) v1.3 Lantern Rite (February 2021). - Xiao (Polearm, Anemo) 5* - Weiwei (Claymore, Electro) 5* - Yaoyao (Catal… https://t.co/XBzWunwsqf
Zeniet
@Zeniiet
Females 1 https://t.co/DzZHIM2mD6
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