I would like to know how to draw qrcode on Waveshare 1.54inch e-paper display. I’ve used that library: https://github.com/ricmoo/QRCode, the example only shows printing on Serial.
You just need to draw filled rectangles in black or white to the display. Try to do it on a TFT first, if you have one. If you use a TFT library with standard Adafruit_GFX fillRect() method, it should be easy to use it then with an e-paper library, e.g. GxEPD.
I would first search for qrcode in the Arduino Forum, I did, but did not see a directly usable entry for TFTs, but maybe this for LCD has some useful info: Encoding and generating QR Codes