Long time user. Experiencing the same issue here with Big Sur and Evernote:
v 10.5.7 build 2171 public
Editor: v114.1.14753
Service: v1.25.2
When i go to export the notes, after about 157 notes or so I get the error " There was a problem and we couldn’t export your notes. Please try again."
Trying again and I get the same error.
I feel like i will be missing hundreds of notes. awful. Sad.