How Do I Fix Google Takeout Photo Dates on Windows?
The full process on Windows, from unzipping the parts to checking the Date taken column in Explorer.
Unzip every part of your export into a single folder first. Windows' built-in extractor is slow on large archives and sometimes stalls, so 7-Zip is worth using. Keeping everything in one folder matters because a photo and its .json file often arrive in different zip parts.
Next, check your timezone in Settings. The sidecar timestamps are UTC and get converted to local time, using whatever your PC is set to, so a wrong setting shifts every photo by the same few hours.
Then fix the metadata before you import into anything or copy it to a NAS. Moving broken files around only means moving them twice.
Install it from the Microsoft Store, or download it directly if you prefer. Choose your Takeout folder, choose an output folder, press start. It writes the real capture date, time and GPS into each photo and corrects the file timestamps, so the "Date taken" column in Explorer fills in and sorting by date works again. Add that column by right-clicking any column heading, and spot-check a few files before you process everything. It runs entirely on your PC, nothing is uploaded, and the first 500 photos are free.