Ukraine has been using COTS drones for some months, with a home made carriage and release mechanism to hold grenades that have been modified by fitting 3D printed tail fins. Brilliantly ingenious and simple in concept, and seemingly both cheap and effective. I believe the modified drones they are using are just a couple of thousand dollars or so, the grenades are ones they already have lots of and one of their backyard workshops came up with the 3D printed fins and fuzing system. Got to really admire their ingenuity.
This video gives an idea of what they were doing about 5 months ago: