The XD cannot display the font 'PingfangSC Medium' correctly.
As shown in the figure, Medium and regular display effects are the same, and there is no problem in other software.
Run-time System: Windows 10
We tried reproducing the issue here, and we are seeing both regular and medium correctly. Please see the image attached. The only thing that could have caused is, you do not have this font on your system. In this case, XD will substitute the nearest font and will show you the text.
Please try installing the font and let us know if it fixes your issue.