Why Does My Phone Gallery Show the Wrong Dates?
Copying photos onto a phone usually resets the file date. Here is how to make the dates stick.
Because copying a file onto a phone usually resets its date to the moment of the copy. Android does this almost every time, and gallery apps that sort by file date show the result.
The photos themselves may be fine. If a picture carries a proper capture date inside it, a good gallery will use that and ignore the file date entirely. The ones that go wrong are the files with nothing inside them: screenshots, chat images, anything from a Takeout export, anything edited in an app that stripped the metadata.
Write the date inside the photo before it reaches the phone and the problem disappears, because that is the one thing copying cannot reset. The app does that, and can copy the finished library straight to a connected Android phone, into the folder its gallery already scans. The first 500 photos are free.