Will it be extra work or confusing for my manager, greater team, and customers?

It shouldn't be.

Job sharing is like a microteam based on complimentary strengths and expertise areas. There is no need for duplication. No need to do individual one-to-ones, partners should be reviewed together, and review each other. They need to be clear on areas of expertise and ownership with themselves, the greater team, customers, vendors, etc. - but each can stand in for the other.

See the Roleshare Guide for the Operational Model and Working Principles example.