Hi Berk,
Thanks for using Syncfusion product.
We have trackball support in Xamarin.Forms Chart as well. Please refer the following user guide to learn about the configurations of trackball.
Note: Trackball will be activated once you long-press anywhere on the chart area. Once it is activated, it will appear in the UI and move based on your touch movement until you stop touching on the chart.
Please let us know, if you need further assistance on this.
Regards,
Lakshmi R.