In the “good old days” (until around the end of 2022) it was possible to connect a Kobo reader to calibre (via USB cable) and copy / save 200 or more books or documents (all in EPUB format) onto the reader with single file transfer. It was even possible to have 500 document saved with a single file transfer.
However, the software updates in 2023 made this impossible - worse, there were database errors on the readers, which even led to the complete inoperability of at least 2 devices.
Since then I have been using Pocketbook devices (in the manner described above) and have no longer had any problems.
This thread is not about whether 500 "real" books or documents can be read in a short time (that's not the application here, by the way), but about the stability of the device software.
Now a student of mine wants to use his reader in a similar way as me. He owns a Kobo Clara 2E. Given my experiences, I advised him against it, but he "loves" his Kobo
Therefore my questions: How do you copy EPUB documents from calibre to the Kobo reader via file transfer? Which of the 3 “device interface plugins” do you use? How many books do you copy onto the reading device at a single time? If you divide 500 documents into smaller quantities, how large are these quantities? Do you switch off the device completely once the file transfer and database update has been successful so that the database can completely rebuild itself?