Itty bitty baby pomegranates just at the stage where they are going from flower to fruit. They are called granada in Spanish. They;re not native to Mexico but you see them growing in lots of home gardens.
Mostly I've seen them in Teotitlan where they use the bark to make a natural dye that produces various shades of brown. More and more, like everywhere in the world, you are seeing the resurging interest in natural dyes. Cochineal, indigo, and caracol are at the top of the pyramid historically when it comes to natural dyes in Oaxaca for their brilliant reds, pink, purples, and blues respectively but there are lots of other plants people are using
(And sorry for the big white arrows on the photos. These aren't videos.)