The Indian market in my neighborhood carries these pictured onions. They have violet skin, white flesh, and light violet layer surfaces. Their flavor is about the same as spherical (ordinary to me) red onions, not that of shallots. Blemishes usually reach the first layer of flesh, so I discard that.
They are mostly 3.5 - 4.5 cm long and shaped a bit like garlic cloves from growing pressed up against each other. Most hang together in pairs but that may be coincidental, as many cloves are internally doubling.
Given the size there doesn't seem to be much room for developing into spherical onions after all, which the store also carries, so perhaps they are not just younglings. Do those things have a name of their own, and is there any difference in application from round reds, be it substantial, traditional, or regional?