Hello,
i.MX 8QuadMax, support up to 4 displays:
Any combination of 2-4 displays of the following 4 displays: HDMI_TX, LVDS0_CH0, LVDS1_CH0, MIPI_DSI1.
Any combination of 2-4 displays of the following 4 displays: LVDS0_CH0, LVDS1_CH0, MIPI_DSI0, MIPI_DSI1.
Regarding the input configuration, I suggest you take a look in section 8.3.3.1 Binding the display port with the input port of Android Automotive User's Guide.
Best regards.