I have save files that I have freshly dumped with JKSV that PKHeX says are "too large". Including saves that were exported by PKHeX itself and successfully imported back into my console.
My most recent files are 1603122 bytes (dumped today), vs 1603146 bytes (a backup file from June, which PKHeX imports A-OK).
I'm using Linux. Both Mono and Wine seem to give me the same issue.
What gives?