Is this project dead?
The merge process compares entries based on their unique identifiers (UUIDs) and modified timestamp. When an entry UUID matches, no matter which group it is in, the most recently modified version will be made the current and the previous version will be placed into the entry’s history.
https://keepassxc.org/docs/KeePassXC_UserGuide#_merging_databases
Is this project dead?
https://keepassxc.org/docs/KeePassXC_UserGuide#_merging_databases