In Finland you can submit your own photo through the internet. All applications are verified by the police so I don't see the issue.
> Such manipulation of photos is typically invisible to the human eye, the researchers found.
[1] https://www.poliisi.fi/passport/passport_photo_instructions
https://lupakuvienvastaanotto.fi/Default.aspx
E: not to mention that the page you linked doesn't even say anything about prohibiting self taken photos.