Gotcha, didn’t realize you wanted to see the tooltip for all series at a given time.
Have you seen this thread [Bug-11636] - XY Chart Tooltip Background Color
The image in the original post looks like what you need but I read through the thread and I’m not 100% sure which tooltips still remain. It looks like they are using a chart cursor. Maybe you could message @milbar to see how he generated that graph.
I know if you associate a series with the cursor prop of an XY Chart it displays the axis values but it I can’t get it to display the tooltips like is shown in the linked post above. I still have some chart implementing to do, I’ll let you know if I see anything relevant.