if your mover-variable is (1.0, 1.0) and you normalize it, it becomes approx.: (0.7, 0.7)
You check for x/y to be exactly 1.0
You should replace == 1/-1 with >= 0.0 / <= 0.0
EDIT: At the moment it would also not work with analog-input, because x/y can be less 1.0
Don't use $Sprite/anims more then 1 time! if you decide to rename it, or make it a child of another node, you have to track down every line with that.
It's better you add
onready anim : AnimationPlayer = $Sprite/anims
So you can use
anim instead of
$Sprite/anims. And if you have to change name/path you only have to change it in 1 line.