Just throwing this out there. A new free online manga called "
Hada Camera", with "Hada" meaning skin in English, has begun being released from this April with a chapter per week. From the looks of things, it seems to feature a protagonist with a magical old-fashioned camera which the taken photos can transform people into the person represented in the photo itself.
So far with three chapters having been released, there has been one transformation event with detailed process sequence that had the protagonist's skinny female co-worker into a more developed girl who he happened to take a photo of.
Main page:
https://www.sunday-webry.com/comics/hadacamera/
Chapter 1 (First TF):
https://www.sunday-webry.com/comics/hadacamera/ep001/
Chapter 2:
https://www.sunday-webry.com/comics/hadacamera/ep002/
Chapter 3:
https://www.sunday-webry.com/comics/hadacamera/ep003/