So what is Xprinter? It looks like all the other cheap generic Chinese printers that I see. Likely this is the reason why. I would imagine Xprinter is just a company that is sourcing cheap Chinese printers and slapping their name on them hence the lack of support or details.
I find that most EPSON XCT commands work but you may need to try different variations. I have a generic Chinese printer and most of the XCT commands work just fine.
I found this you can try it and see if it works for you.