Is your feature request related to a problem? Please describe.
I am building a page that will have multiples charts(elastic/kibana#68176 for 7.9), they will all have the same x value. I'd like to have a way to sync all tooltips so when a user hovers over any chart the others tooltip would be shown.
Like the APM transaction page.

Describe the solution you'd like
We could have a hoverX property that would be used to pass in the current position the user is hovering on another chart.

Checklist

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