Anyone has tried 19x9.5 et45 on the front? Will it rub on the strut? If it doesn't, will it fit in the back?
Haven't tried a 9.5" on a MK7 myself, but that is a lot of wheel. Strut clearance would really need to be checked with the specific wheel you have since rim lip designs could change fitment, as well as shock/coilover diameter. I ran a 19x9.5 ET45 on a MK6 (CC) and I needed to run 3mm spacers minimum up front because of the rim lip contacting the coilover.
As far as the fender would be concerned, if you ran -2 or more camber front and rear with a stretched 235/35-19 (Conti ECS tires are spec'd from 8-9.5" wheels, I just checked) or possibly up to a 255/30-19 depending on the tire width/profile you should be good depending on what you're trying to do. I ran 10mm spacers on my 18x9 ET45s which is 3-4mm more aggressive and that was fine as a daily setup and even some light track duty. In the rear, I don't like that much poke but I also don't run that much rear camber, but it should be fine as long as you don't run too much tire.
For a street cruiser setup or with bags it would be doable, but if this was going to see track time I think you'd be better off with something narrower because you would rub easily in hard corners.