Arkham versions? The Skulls are kind of a joke, they're unable to dodge the Honey Bee rocket, they have no minds of their own, no skill or intelligence and are essentially zombies with better physical stats. Anyone here can pretty much disarm them and use their own machete's against them
The camo Skulls would be more of a problem since they're snipers but could be taken out easily via stealth in which all of Team Batman excel at.
So we're using the Arkham game versions of the characters? Also is it 5v5 or 5v15 as the later is more of a challenge. The mist unit goes down pretty hard as there pretty much just faster titan users: Batman could probably solo these guys. The armor unit would be the biggest challenge due to their load out while the camo unit would be an interesting fight due to having to rel on stealth for the encounter.