Experiment

test note title:

!@#$%^&*()_+{}[]|;',./:"<>? `~

exported HTML filename:

!@#$%^&*()_+{}[]|;',._/"<>_ `~.html

exported resources folder name:

!@#$%^&*()_+{}[]|;',._/"<>_ `~.resources

Conclusion

Evernote will change the following characters in note title when exporting to HTML files:

  1. / -> _
  2. ? -> _
  3. : -> /