This is a quick and dirty script to migrate Simplenote notes as notes in TickTick and Remember The Milk tasks as TickTick tasks. This needs only the python stdlib.
Test with example file at
$ python3 migrate-simplenote.py example-export-simplenote.zip
Wrote 2 notes to ticktick-from-simplenote.csv
Run above command with exported zip file and you will get ticktick-from-simplenote.csv which can be imported.
They will show up in a new list called Imported Notes. Edit and change its type to Notes List. Select all notes with Shift+Click and Convert to Note. This could not be automated. Then change sorting to By Modified Time.
The creation and modification times will be current time, but order will be correct.
Clean up the extra folder and list.
Test with example file at
(venv) jesvin@jesvin-Inspiron-5559:~/dev/ticktick-migrator$ python3 migrate-rtm.py example-export-rememberthemilk.json
Wrote 5 tasks to ticktick-from-rtm.csv
Run above command with exported json file and you will get ticktick-from-rtm.csv which can be imported.
Import into TickTick as described previously.