greetings gawriele,
Unfortunately, the wallpaper settings is system based. The launchers kind of sit on top, they are just front-ends.
I don't think there is a way to have the wallpaper change based on which launcher you use...well the app, Tasker, it's supposed to be a pretty powerful program. It allows you to control most aspects of your phone. I can't say for sure, because I've never used it. You can look into that.
The only semi automated way I can think of doing something like this, is to use the app. Multipicture live wallpaper. This app will allow you to have a different wallpaper, but your will have to do a little work each time you change launchers.
1. Make a folder..something like Launcher Wallpapers.
2. Inside this folder, make separate folders named after the launchers.
3. Place the wallpapers you want associated with each launcher in their proper folder.
4. In the settings for multipicture live wallpaper, can choose the folder for the app to use.
This is a cobbled together approach to what you want. It's not hands free, which I suspect you desire. The benefit to this though, is Multipicture will not only allow you a fast selection of your wallpaper, you can have a separate wallpaper for every home screen if want.