Kisekae Yuka-chan

Meet Yuka, a 6th grade fashionista who thanks to her ability to put together just about any outfit on the fly can disguise herself as nearly any age she wants. She’s just a little bit crazy, and has been known to pass herself off as the older sister of her actual older sister. This manga is the tale of her life…

(Source: Animeraider).

Included one-shots:
Volume 1: Kisekae Summer