Complex sentence: She is an accountant in real life and is a great asset to Shiroe's plans due to her ability to negotiate with others, but it is not known whether her skills at cosplay in Log Horizon are the same in the old world.
Split into simpler sentences: She is an accountant in real life and is a great asset to Shiroe's plans due to her ability to negotiate with others. It is not known whether her skills at cosplay in Log Horizon are the same in the old world.