Use "System Compare Two Values" condition. left(Character.AnimationName,4)="Anim"
Be aware, that this condition doesn't pick instances, if you have many character instances, then use "System Pick By Evaluate" instead.
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If there are many "AnimN" animations and you want to check if only animation 1, 2 or 3 is playing, then you can use this expression:
left(Character.AnimationName,4)="Anim" & int(mid(Character.AnimationName,4,1))<4