I honestly didn’t notice until someone on reddit pointed it out but look:


Look closely



So the boop thing isn’t just Sombra being cute, it’s also a subtle way of reinforcing a threat towards Volskaya’s daughter (if she didn’t get the message from the rest of Sombra’s visit). Which is pretty clever… somebody like Volskaya could be willing to destroy herself if she thinks it might be for the good of her people, but is she willing to sacrifice her daughter, too?