When they realize that mealworms are edible, you will just be able to drop them in. I like to use a shoebox size sterilite, put in the mantis, and drop the feeder in, if their home container allows crawlers to hide.
It is not too much work if you only have a few mantids. It gets really tedious when I am out of flying insects and have to feed mealworms to 20+ mantids. :mellow:
I was just doing it for party tricks....when I tell people I have a trained praying mantis they can hardly believe it.....Typically he eats crickets and flies and anything else I can catch.