Graphics.drawString not working on 1v98?

Which board are you using? I just tried here on a Pixl and also a Pico and it seems ok:

>var g = Graphics.createArrayBuffer(8, 8, 1);
=Graphics: {
  "buffer": new ArrayBuffer(8)
 }
>g.drawString("X");
=undefined
>g.buffer.toString()
="5,5,2,5,5,0,0,0"

I'm not quite sure I understand about the centering - the default text is normally 4x5 characters so -2,-2 sounds ok, perhaps 1 pixel off depending how you choose to round.