Используйте приложение APKPure
Историческую версию User Dictionary Backup можно получить на Android
Резервное копирование пользовательских данных
UDB (User Dictionary Backup) allows you to Backup and Restore words you stored manually in the Dictionary. It also allows you to import words from a .txt list of words (each in a new line, placed in the "UserDictionaries" Folder.)
**This App might not work on Phones which provide their built-in Backup/Restore options for the User Dictionary.