The new combined panner in cubase 10 confuse me a lot. Why change the old one who it was so clear? Why complicate the simple things?
Need further explanation of your concern.
Regards 
Both the Stereo Combined Panner and the Stereo Balance Panner have been in Cubase for many versions and are not new with 10. You can switch between them on the Channel in the mixer. You can also set one to be the default in Preferences. If you are seeing the Combined when you expect to see the Balanced then most likely the Preference got inadvertently changed.
The two different types of panners behave differently and are useful in different circumstances. If you search the forum you’ll find at least one thread going into these differences.
I mean it is not easy understand how to set it. The previous one version I remember it was better. Anyway in the end I tried double click and I resolved all… So this is just my opinion, I prefer the previous version (maybe cubase 8) instead the news one.
Thank you
But there is no “previous” version - they have both been included in Cubase for many years, long before Cubase 8. Just because something is new to you, does not mean it is new. Change the Default in Preferences/VST to the Balanced Panner and you’ll be back to the way you were.
And while a Combined Panner is a bit more complicated to use that’s because you can accomplish things with it you can’t with the Balanced panner.