Complex sentence: Paying players who purchase a copy of the full game will be able to play as all classes from all factions.Also, players will be able to buy specific factions from a game store that will also sell faction appropriate cosmetic items, operating via a microtransaction service.
Split into simpler sentences: Paying players who purchase a copy of the full game will be able to play as all classes from all factions. There will also be an in game store that sells faction appropriate cosmetic items, operating via a microtransaction service.