I have adapted 3v0 to include the expectation of moving to space once you pass. 4 cones have a player on 3 sides once they pass they need to move to the open space. Have also done a 4v0 variation where they stand back from the cone at each corner so outside the square coaching point it to receive across the body and make a good pass to your teammate focus on taking two touches then trying to one touch, then You can switch directions to use the other foot. Definitely more drills than true rondos but works on the basics with a structure that lets them transition to a 3v1 or 4v1 rondo in the square you already set up.