I haven't seen the Wim Wenders
film but I can easily imagine Handke as a rather dull screen writer.
The effect Handke produces in his short novels ( most of them are about 35,000 words or shorter) depends on a very careful accretion of simple descriptions building a rather ghostly atmosphere overall. You feel as though the acuity of social commentary possessed by Fitzgerald in "The Great Gatsby" has somehow attached itself to a parading set of Pirandello characters in "Absence", a book you might want to try sometime.
Handke's nonfiction book on the Serbian side of the Kosovo disaster is also a good introduction.
Handke is very scrupulous about not attempting "surrealistic effects", but the effect is often dreamlike nevertheless. The simplicity of his sentences produces a Paul-Delvaux-like clarity of vision, but everyone ( his characters) might just as well be wrapped in filmy white chitons, and the background sky might be a cerulean tending toward the green choma . . .
Handke doesn't possess the grand, operatic scale of Sebald ( and I mean those epithets in an unaccusing way), but they both possess the ability to point their authorial "lenses" at just the right scenes and objects to give us a sense of displacement from the real. Or, to put it another way, they show how unreal the real is.Or how we simply miss the connections, the links between things that give the "derangement" Rimbaud recommends without the use of drugs.