Hello,
Yes, mega menus were created using static blocks and can be edited via Dashboard > Static blocks.
Here is the video – https://youtu.be/7QluEYxznKs , but in your case, it will be Elementor editor, not WPBakery.
You can import demo sections, go to static blocks > click on create new > edit it using Elementor > click on Studio icon https://prnt.sc/vyORpIpRpsIV > filter to find mega menus then insert it https://gyazo.com/2046dc2e98b5e45a99a57dafac94aea3 and edit depends on your needs.
Regards