This is a demo tutorial. While there is no step-by-step commentary available (yet), the live demo below is fully functional. Feel free to open it for full source code.
This demo shows how we can programatically trigger display of the rollover tooltip on a MapChart by setting respective polygon's isHover property.
See the Pen amCharts 4: Triggering map polygon tooltip via API by amCharts team (@amcharts) on CodePen.24419