Video Playback On MMI?
 

The DVD player while the car is parked.

You can also play certain video-files from an SD-Card.

Yes. You can play video while driving too, I've sucessfully, done on my friend's A4 using an Rooted Xiaomi phone.
https://forum.xda-developers.com/and...3734180/page20

https://drive.google.com/open?id=1-C...Qmcpok_NFvZhft

do you need vehicle in motion enabled to do that?

Nope, there's no need to modified the car itself. The only thing to do is an rooted android phone and AA mirror unlock apk.

You can move from car to car. Works on any car that has Android auto on them.

First of all what year Audi do you have? I have a 2014 Audi A6. I ordered a device that plugs into my ODB port where I was able to disable the VIM (Video in Motion) restriction. Then you will need:

Audi AMI RCA Cable Adapter (I bought OEM one)
RCA-HDMI Converter
3 RCA Male to Male Adapter
ScreenBeam Mini2

So basically all you do is plug the Cable adapter into your AMI port in your arm rest. use the 3 male adapters and plug into the RCA Converter. Plug in your Screenbeam to the Converter. You will most likely need a dual port power outlet to power the screenbeam and the converter.
I use a Samsung phone which I can then send to the screenbeam which then mirrors my screen to the Entertainment Screen.

Now if you have an iphone you could probably buy a lightning to HDMI adapter and an HDMI cable that you could use in place of the screenbeam.
Or if you don't want to use a screenbeam you could probably use a USB-C - HDMI cable as well.

You might also need to set your RCA Converter to NTSC and Once you have it all plugged in and powered, go into the Settings menu (while in Media), and scroll down for the options to switch the input to NTSC (vs. PAL) and 16:9 aspect ratio. The phone mirror function would not work when I used PAL and the screen would be compressed if you chose 4:3 ratio.


Hope this helps.