Did you check both homestead chests? Did you try using the 'take all' button or hotkey with the homestead chests, and checking the character's inventory for it?
I tried this in a save at the end of the game (both main characters), and it worked fine.
If you still can't find the sabre in your latest save, please email supportdos@larian.com, with a description (or link to this topic) and a save before and after sending the sabre to the homestead chest (or a Dropbox or Google drive link, etc).
For Windows you can use the report.zip file generated by the
D:OS EE Analysis Tool.
Extract the zip file somewhere and run AnalysisTool.exe. When that loads, browse to the install folder (if it is not automatically detected), optionally run the tests first, and then generate a report (it will be saved in the same location as the Analysis Tool).
The report will contain system and game information, as well as your saved games. To reduce the file size, you can delete most of the saves from the zip (double click the zip file to open it in Windows Explorer, then browse down to the savegames and savegames_patch folders).
For OSX, saves can be zipped by right clicking the folder(s) and selecting Compress, in the folder:
~/Documents/Larian Studios/Divinity Original Sin Enhanced Edition/PlayerProfiles/<ProfileName>/Savegames_patch
Linux is similar, with the saves in the home directory.
