@Bronydog
It’s implying they celebrate Halloween in Eventide, alongside holidays like Technology Day, Unity Day, the Barbecue Festival, Day of the Dogs, and Day of the Dead :D
Since she’s from the technologically advanced Eventide, she likely has a device on/in her that mimics various forms of magic so, for Eventide, she’s normal.
@Bronydog
I’ve technically made normal ponies in the past. Like, there’s nothing objectively abnormal about Fake Twilight outside of his passing resemblance to real Twilight :P