Persistent Charges Visible for Hidden Characters in AW in the Matchup Screen
While it is improved over awhile ago when persistent charges could be viewed when viewing the map (this got fixed awhile back), you can still see if a hidden champ has persistent charges once you reach the node and do the matchup screen where you select your champ.
Given persistent charges are still limited, this usually allows attacker to know who the defender is and they can select who provides the best matchup for them. For example a mystic with 0 is morningstar while a mystic with 3 is Meph, a mutant is sabertooth, a science is Sentry or Modok (more likely Modok), etc.