Electronic Girl is one of the three skins released in the multi-part Techno Kat's Shop offer. It could be purchased as part of an item deal in mid August 2018.
Electronic Girl could be purchased for $9.99 in a limited time deal that included 16000 coins. It was not available for individual purchase and may not be available for purchase in the future.
Details of this skin may vary depending on location, platform or time.
Note: Electronic Girl was released again for a limited time in The Carnival Collection offer in late February 2020. This time Electronic Girl could be individually purchased for 3100 coins.