The following steps will help you import your notes from Joplin easily.
Open Joplin app on Desktop and click on
File and select
Export All -> JEX - Joplin Export File and save it in desired location.
Go to Notesnook Importer and select
Joplin from list of apps.
Drop the .jex backup file you exported earlier from Joplin in the box or click anywhere to open system file picker to select the backup.
Once importer completes processing, download the .zip file.
After you have downloaded the
.zip file, go to Notesnook app > Settings > Notesnook Importer and click on “Import from ZIP file” & select the .zip you downloaded earlier.
Once importing completes you should see all your notes in Notesnook. If you face any issues during importing, report it on github.