[Solved]-Highcharts - manually trigger hover event on a point-Highcharts

To give a more direct answer (e.g. for then you don't have access to the highcharts instance):

you need to create a mouseover event and give it proper pageX and pageY attributes before you trigger it.

Here is an example of how to select (hover) the last valid point in series programmatically:

  // Find last not-null point in data
  let last = data.indexOf(null) - 1;
  last = (last === -2) ? data.length - 1 : last;
  const lastPoint = this.series[0].points[last];

  // Trigger the hover event 
  lastPoint.setState('hover');
  lastPoint.state = '';  // You need this to fix hover bug
  this.tooltip.refresh(lastPoint); // Show tooltip

Full JSFiddle exapmle

Just to add an important information:

For StockChart this solution doesn't work:

In this example you have to replace this:

chart.tooltip.refresh(chart.series[0].data[i]);

to this:

chart.tooltip.refresh([chart.series[0].points[i]]);

One possible solution is available here.