Well, of course it’s not going to be an easy peasy job since the car is 22 years old.
The bolt holding the fuel pump is just spinning even after soaking it with WD-40. Could not get a mirror in there since it’s tight to see what is behind the strap (a square nut, maybe stil don’t know ? Wtf was audi thinking?).
Anyway, I was still able to replace the filter as the hose going from the fuel pump to the filter can be disconnected at the fuel pump and is somewhat easily accessible.
A few pointers: make sure the strap holding the filter can be loosened , then tighten it back up, pop the hose going out to the front of the car (from filter), pop the hose at the fuel pump going to the filter (its long-ish ) then undo the filter strap then slide the filter with the long hose towards the front of the car while you twist a bit as that hose going to the fuel pump is like an S shape.
On the bench you can transfer the S hose to the new filter and slide the filter back in while you twist it. Pay attention to the arrow on the new filter, has to point towards the front of the car as the pump is sending fuel to the injectors.
Grab a beer and pat yourself on the back
this is how I did it last time, no need to remove the fuel pump when changing the filter 