In order to plot a Passing Bablok fit (or any other fit from a modeling platform) in Graph Builder, first save the model equation as a column in the data table. From the Bivariate platform, use the Red Triangle to Save Predicted. To fit+export many series at once, hold down the Ctrl key while using the Red Triangle Menu.

Then, in Graph Builder, add the fit equations in the Y-axis role, the same way you added the data points. Use the Formula graph type for best results:
