The new series “Mrs. America” is about the 1970s battle over the Equal Rights Amendment. It’s available via FX on Hulu. Dahvi Waller created this series after she wrote for “Mad Men” and “Halt and Catch Fire.” She talks about tackling the complicated character of Phyllis Schlafly, the woman who led the movement that ultimately blocked ratification of the ERA. She also shares the complications of finishing post-production while under stay-at-home orders.