ZingChart: On multi-series charts, can I create individual crosshair labels for each plot?

Yes. In the plotLabel object, add a multiple attribute and set the value to true. This will break apart your crosshair plot label so that a label appears for each series.

Next, you have the option to individualize the text and styling for each series. Go to the series array. In each object, create a guideLabel object and provide your desired attributes. In the below chart, individual font colors were specified. Refer to the Crosshairs Guide Label JSON page for a full attribute list.

Example: https://demos.zingchart.com/view/9AUXUDOW

Documentation

Interactive Crosshairs Tutorial
Crosshair Plot Labels JSON Syntax
Crosshair Guide Labels JSON Syntax