Trying to upload the non-armpit hair version flags it as a duplicate of this one.
When you try to upload images from a set, you need to link to the specific image, not just the page for the set. (You're probably sending the exact same url even while looking at different images.) See the wiki page on uploading from pixiv (the expand part) for details.
What you want is this: https://i.pximg.net/img-original/img/2019/07/14/22/13/59/75723368_p1.png (The first image is "*_p0.png", the second is "*_p1.png", and so on...) Click on the "1/2" at the top right for the preview, then when you get the full-size image, right-click and hit "view image" or "copy image location".
When you try to upload images from a set, you need to link to the specific image, not just the page for the set. (You're probably sending the exact same url even while looking at different images.) See the wiki page on uploading from pixiv (the expand part) for details.
What you want is this: https://i.pximg.net/img-original/img/2019/07/14/22/13/59/75723368_p1.png (The first image is "*_p0.png", the second is "*_p1.png", and so on...) Click on the "1/2" at the top right for the preview, then when you get the full-size image, right-click and hit "view image" or "copy image location".
So I open the individual images in browser and use the bookmarklet on the image rather than page?
