Unfortunately I wasn't able to get a good clean image of Coco or the other gen 4 and gen 5 girls in their idol outfit since it was only ever shown in 3D streams. Watame it's the only one with it since there was 2D images on her concert website.
https://www.reddit.com/r/KiryuCoco/comments/pjzy09/idol/
https://twitter.com/um_eoji/status/1332606035639427073?s=20&t=zDXKfeQOqKM3tc5Vck...
https://twitter.com/norealist_holo/status/1505208781701271556?s=20&t=43kcZ879dqU...
https://twitter.com/stoppachan/status/1503340759336230920?s=20&t=IfOojdTmcsUQDwK...