PowerDeleteSuite. I used this when things went hot with Reddit. You can even edit your comments before deleting them, best part for you, you don't have to delete them. (Hopefully Reddit haven't countered this).
It works, but it takes a long time, and then Reddit un-deletes your comments. Make sure you set it up to edit your comments before deletion. A message like the one in the image is a pretty good choice.
Is there a more effective one, that slowly edits all your comments a little bit at a time so it misses their detection over a period of weeks/months? Like scrambling/nonsense sentences.
There was a book whose card when blunk when they looked up.
Like completely non sensical but a real sentence so it would be hard to detect.
Look at the issues and you will notice it only works on comments visible from the profile page and that not all are visible. It appears that someone made a python script to solve this problem but that you need an API key to use it.