Waveshare library (1.8" LCD) is so weird

I strongly advise installing Bodmer's TFT_eSPI library via the IDE Library Manager.

It takes a little effort to choose a suitable Setup file.
Then run all of the library examples.

Yes, Adafruit_ST7735 should "work" but never as well as TFT_eSPI

No, I don't have your Waveshare display. Waveshare examples probably work but will be slow.

David.