@noiob thank you
@confusedcharlot If you want to follow everyone on both, download and import in each direction! You can choose to add instead of overwrite the list.
If you want to do manual reconciliation, IWRC the downloads are just CSV so maybe you can pop them into a spreadsheet program or something. Or even text diff them.
@confusedcharlot you could just export them on both and import on the other respectively