Export PNG option
I had a problem recently, when I export a Photoshop image in PNG and re-import the same image in XD and export the same image increases the size of the KB. I discovered that PNG with photoshop exports with 24bit and XD exports to 32bit, causing the image to increase its size. It would be important to think about the export in the part of the PNG with option of 8bit, 24bit and 32bit so that this increase does not happen.
Abhishek Das commented
Thank you for posting.
The size of the exported PNG depends on the platform you are choosing in "Export For" option. But currently the option to change between 8bit, 24bit and 32bit isn't supported by xd. You can ask for feature request.