Graphing two counts onto same visual with multiple date columns

katemke , If they are two tables - no column, with date table you can have two active join and you can work with count and sum measures from both tables

If they two dates from one table. One inactive relationship need to be activated using userelationship

And you need use common date from date table on slicer and axis

example

calculate( SUM(Sales[Sales Amount]),USERELATIONSHIP ('Table'2[CreateDate], 'Date'[Date]))

https://community.powerbi.com/t5/Community-Blog/HR-Analytics-Active-Employee-Hire-and-Termination-trend/ba-p/882970

https://radacad.com/userelationship-or-role-playing-dimension-dealing-with-inactive-relationships-in-power-bi