Don't change this back to Reimu. Unless something in Yohane's commentary says otherwise, this isn't her.
He sticks to Sendai's outfit of a hakama with hip vents and Reimu's outfit consisting of her red skirt.
It is Reimu cosplaying as Kanako, the same way Kanako is cosplaying as her. Yohane draws Sendai with black hair and a noticeably mature face. Meanwhile he draws Reimu with brown hair and a noticeably younger-looking face, much like this picture.
Also his commentary does say that it's Reimu and her ''mother in law'', i.e: Kanako, because Yohane pairs the former with Sanae.