What SupportiveEntity says is possible if you want to change content based on input device, not platform. That does not answer the question since for example a PS3 supports a mouse and keyboard as well as a PC supports a controller. It is possible to detect such a change though in c++ using an InputPreProcessor which is very easy to do. CommonUI implements such a thing and a widget which responds to a change in input device but it’s an experimental UI framework on top of the existing UI framework, a bit of bloat.
The UGameplayStatics library has a method which returns the platform name as a string to blueprint, maybe you could use that. Since you don’t actually “change” the platform after the game starts, you could just check for the platform name on the start of the game / BeginPlay or similar single event and load the right asset there.
How to see what platform game is running on? - #6 by anonymous_user_75f3f229