I have them and they’re controlled by the MMI on mine. If I change brightness for door cards etc it changes the handle LEDs as well.
my car is a 2016 so probably something Audi has removed to scrimp on costs as per.
I’ve done a few things on mine with Carista
Beep on lock / unlock
Rear DRLs - a must for me as it looks awesome
Auto high beam - great feature and works surprisingly well.
I couldn’t get Lane assist to work for me and I’ve not seen anything relating to ad blue or parking break.
If you like that new car smell which is very solvent based (glue and leather) I urge you to try chemical guys new car smell air freshener. This is the closest thing I’ve ever found to getting my car to smell like that. 2/3 squirts on each floor Matt and you’re set.