Hi TaeWook,
Greetings from Synfusion.
We can render a text in the center of the Chart by using the
coordinateUnits property in annotation in the Accumulation
chart. However, we have created a simple Core application to demonstrate the
same and it can be downloaded from the below link.
Sample link: https://www.syncfusion.com/downloads/support/directtrac/general/ze/PieChart137261113
Please find the online demo sample link for your reference.
Online Demo link: https://ej2.syncfusion.com/aspnetcore/Chart/PieLegend#/bootstrap5
Screenshot:

Kindly, revert us if you have any concerns.
Regards,
Swetha