'act as such' is correct and usable in written English.
It can be used to suggest that someone do something in a particular way. For example, "If you want to be successful, you must act as such."
Treat them like citizens and they will act as such.
"But we're not the police and don't want to act as such".
Speaking at a mosque, the pope said Christians and Muslims were "brothers and sisters", and called for them to act as such.
Passport photos, or those on national identity cards, can act as such galleries, as they can be rendered by EBGM into usable 3D models.
Anyway, she started dancing with Stephen, doing "bits and bobs" around the place; they weren't an act as such, it wasn't a case of The Deans Do Dagenham, but people seemed to like it and they got paid.
This is a common technique, a way to create sauces from ingredients that would otherwise be too thick to act as such, but without using more olive oil or the other standby, tomatoes.
The current system of surcharges probably acts as such a deterrent in local government.
It is this that has acted as such an ominous 1930s-style recruiting sergeant for Europe's extreme right.
"We had 34,000 here in the cup the other night and they're so noisy and this place acts as such a soundboard that it feels like 90,000.
There is, in fact, a spark of chemistry between Heigl and Butler: it's testimony to the ineptitude that the film itself acts as such a wet blanket.
Yet the same media were present at the time these acts were committed.If the Somalis saw the UN troops as invaders, it was because they acted as such.
