Old-Fashioned style - gloves and a trowel. Or best - a chair in the shade with a cold drink while supervising your kids.
My child is grown, but I have arthritis and chronic Lyme and this heat is 95, feels like 105, very humid, yuck. Not much shade unfortunately. Thanks.
normally, you have to wait till around the middle of
February and apply a crabgrass deterrent before they germinate. Otherwise, you are just creating more work for yourself.
But can you put that in th egraden beds with roses, evergreens and perennials and bulbs? I have a lot of weeds now after clearing it all out in February, March and April! Ugh, exhausting!
I am pretty sure you can as it affects only the crabgrass particularly if it is being it produces growth/seeds. It does not affect surrounding grass when applied to lawns. Good luck
Then on a serious note, there are suggestions of spraying a vinegar solution on the plants you don't want - Make a shield out of a waxed paper plate so you only hit what you want to die. Pour boiling water on the plants to kill them off. Contact a local high school - there are kids looking for projects for extra credits on their school records to make their college apps look good. Contact your local senior center - there may be swaps you can do - bake cookies/food or make items in exchange for yard labor. Take care of yourself.