Unlike photos, videos do not contain any internal metadata describing how/when/where they were first taken (EXIF data). Therefore, when exporting any kind of video from Apple Photos the files do not contain any information about when that video was actually taken.
My Android device / Google Photos gets around this by setting the Modification Time of the file to the date the video was taken. This is finnicky because if you, well, modify it later that date will change. But it’s better than nothing.
First I exported my videos from Apple Photos by clicking
File > Export > Unmodified Originals. On the window that pops up, you can check a box that exports the
.xmp files alongside the videos. Do that.
.xmp files we can gleam the original shoot date and write that to the video file itself. Unfortunately the XML parser
yq could not work with the weirdly tagged nodes.
Python to the rescue:
Depending on where the video was taken, you may want to alter the timestamp to account for a different timezone.