Joe_Hartzel No root = no real export/import possible for the system personal dictionary.
I have to disagree with you, since I just tested restoring the FUTO Keyboard backup, and it works. It replaces (important detail) the system-wide personal dictionary on import, and clearly says so when you're about to do it.
This demonstrates it is possible to create a personal dictionary backup app. FUTO Keyboard declares these relevant permissions:
android.permission.READ_USER_DICTIONARYandroid.permission.WRITE_USER_DICTIONARY
Found this Android developer guide on content providers which uses the User Dictionary Provider in its examples, which demonstrate how to programmatically interact with the system-wide personal dictionary.
Joe_Hartzel Best non-root option is to use Gboard or SwiftKey, since they sync personal dictionaries across devices.
Sync is not export. I don't sync anything to my Google account. Gboard has its own personal dictionary with import/export functionality though, which I've been using for years. It also produces a plain text file, so it shouldn't be too hard to convert that to the format FUTO Keyboard uses and import it.
Consider this SOLVED. And if anyone knows of—or has created—an app that's just a system-wide personal dictionary manager, I'd love to hear it!