These are the wallpapers used on the home screen of Ubuntu Touch / UBports 20.04 Linux smartphones/tablets. This is from a early Development version release in May 2023 on a Sony Xperia X (Suzu).
Most are repeats of the 16.04 wallpaper pack. Photos from Ubuntu Touch 16.04 are listed here (They were all included with 20.04):
https://archive.org/details/ubuntu-touch-ubports-16.04-wallpapers
These files are located at "/usr/share/backgrounds" on these smartphones. Can use adb shell to copy the files to the ~/Downloads folder then plug your phone into the computer to copy them out.
Update March 2024: I posted a mirror of these photos here:
https://wallpapers.fandom.com/wiki/Ubuntu_Touch_/_UBports_Wallpapers