Editorconfig supports off as a valid value for max_line_length (see https://github.com/editorconfig/editorconfig/wiki/EditorConfig-Properties#user-content-max_line_length)

Current code only sets the Prettier property printWidth if max_line_length !== "off":

  if (editorConfig.max_line_length && editorConfig.max_line_length !== "off") {
    result.printWidth = editorConfig.max_line_length;
  }

Ideally max_line_length = "off" should be supported, maybe with a very high value. Also other non-numeric values for it should be discarded.

I can raise a PR if this issue makes sense to the author and contributors. Please leave your feedback ;)