The keyboard text replacement entries or shortcuts in #iOS and macOS are synced with iCloud. The data is not end-to-end encrypted and there is no option to turn the syncing off.
Consider reviewing your shortcuts and delete the ones you deem sensitive. We asked Apple about how users can exclude this data from being synced with #Apple servers in January. We haven't received a response yet. Remember that Apple is obliged to hand this data to law enforcement given a court order. #privacy#infosec
