My husband and I both live in NJ.
He works in PA.
I work in NJ.
For the NJ state returns, should this be my income only and the PA state form be his income only?
Or should both incomes be listed on both state returns?
If by work you mean he is an employee, NJ and PA have an agreement sourcing employment income where you reside, so both your incomes go on your NJ return(s).
If you mean any other kind of income-producing activity, such as a contractor, sole proprieter, partner, S corp, nonelecting LLC, active investor, etc., tax treatment may different and is very likely more complicated.