Well, I think it can be done.
The data table had to be modified...see the attached table. I then had to group first by Age, and create the linear regressions, then on Group, and then Group again with the Sex column, and then generate those regression lines.
Finally in the data table, there is a new column called Column 5, which is a composite of the Age and Sex values. It is used to generate the row states for the rows, matching to the legend colors and markers set for the 2 groupings.
Not very pretty in getting it done, but.......it was possible
Jim