Is it possible to create a port or wrapper with PlayOnLinux, like you can with Wineskin Winery?
I want to create a simple solution, so people can download my software for Linux without the hassle of installing Wine etc.
How to approach?
I'm not sure it makes sense to use PlayOnLinux if you want to distribute one application. You're probably better of if you build a snap with everything needed and provide a simple installer.
Generally, I don't see the issue of installing Wine etc. because your package management will take care that it's installed (or the PoL scripts if you need a special version).
If you want something like a custom app store, you should have a look at PoL5. It allows you to provide a custom script repository and GUI.