Whatever you provide to them for free, stop. No more free ride. They're freeloaders.
You and your husband need to get on the same page about this or it won't work, but you have to start treating them like adults. They're not children and the way they're being treated (or have been treated) is giving them an extended childhood. What they need is on the job training, so to speak. If your husband doesn't want to kick them out and be the bad guy, you can make it easy for them.
You can print out rental agreement contracts that specify exactly what they're responsible for in the house. It would include rent such as they would have to pay in a one-bedroom apartment including their portion of utilities. It should also include that they do their own laundry, buy their own food, do their own cooking, and be responsible for household chores and yard work. Remove them from the family cell phone plan if they're on it. If they refuse to sign the rental agreement, then inform them it's the same as deciding to move out in 30 days. Include in the rental agreement that if they violate the agreement that will give you the right to evict them within 30 days. If they don't pay you, you will evict them. If they don't do their chores, you will evict them.
And you'll have to follow through.
They'll either comply or when they see you're serious they'll scramble to find their own places ASAP so that they don't have to live under your rules. No more hand holding on the legal issues. No hand holding on college. They're beyond an age where college should be an incentive or held over their heads and definitely beyond the age where you are obligated to pay any portion of their college. You've been paying their way for them to live at home. That could have been money put toward college. Oh well. If they got to college, let them do it on their own now.