I mean, there's always the
AC Pattern Tool, which can turn an image into an animal crossing qr, but you'd still have to take a high-quality screenshot of your map, upload it off of your switch, crop it, put it into the tool, and then download and scan that qr using the nintendo switch online app.
The result would probably be a little more low-quality and a lot more effort than drawing it yourself, but it's an option!