We don't have a way to do this natively, so you might need to look into third party options for this. I'm not aware of any services that offer exactly what you're looking for, but one option could be Board Export which allows you to export your checklists and there may be a way for you to work with the data to gather those that are not yet checked.
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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