Voyage
Is it bannable by system? no
Make sure your level is high enough (I'd say Lv 400+ if you want to complete all the stages through the top) . Because anyone in the game who follows you, can see which stages you are at. You don't want to be seen at the top while your level is still low. Even though I never saw someone got banned from completing the Voyages at low level, but keep it that in mind.
Mirror
Is it bannable by system? also no
But anyone can see your latest loadout when completing a stage. I've noticed that cheating in Mirror is occasionally being discussed by Japanese player on twitter. I have a trick to this, though I haven't tested if your loadout is replaced in changelog automatically if you clear the same stage or not. What I do is clear all stages using anything that I got, after you complete all stages, reset stage one by one using loadout that makes sense, what I mean by that is your weapon/armor is *7 max, also your monsters is *7, capped +7, stone installed, you know what I'm talking about. That's what I did back then.