Best low cost software for lightsaber effect on a macintosh? I'm interested in creating lightsaber effects with a Macintosh on home videos with my children.

What is the best low cost software for recreating this effect today? I don't have Adobe CC, and have no desire to subscribe to it, nor do I have Final Cut Pro X.

Does iMovie support this effect? Are there any good free or cheap rotoscoping or canned effect programs to accomplish this?

Edited to add: "Would the free (non-commercial) edition of Nuke for Macintosh" be a good solution? (I discovered it after asking.)

Thank you.
You could try the HitFilm Express 4, they have the sci-fi pack (25usd) which contains the VFX you want and specific tutorials for lightsaber (https://hitfilm.com/express/the-force) and it works on mac :)
Link: https://hitfilm.com/store/hitfilm-4-express