@Ron-Smirnov No you can not use it for 3rd party apps.
Until Android N comes out there will be no 3d touch for Android.
Sad news, as Meizu does things different, mostlikely 3rd party apps won´t support the Pro 6 later anyway. But this will be a problem for the future.
Don´t buy a Pro 6 if you want to use 3d touch, that feature is useless.
@Ron-Smirnov Yes, got that part.
The problem is that Meizu does not take Android serious. They are a bit stupid in China, when it comes to Google.
And so Meizu dreams that people will make apps for the very special Meizu-3d touch -> what won’t happen ever.
Best is to wait for Android N to support 3d touch and then get a phone with it.
However that doesn’t help you. :(
You can hope for the flyme-tools what’s an xposed frame-work to do some magic, but other then this I don’t know what you could do with the Meizu-3d touch for Android Apps.