She is a very capable black woman. How would I make this nonracist and nonagist?

She is a very capable person.

To make the statement nonracist and nonagist, you can focus on the individual's capabilities without mentioning their race or age. Here's an alternative statement:

"She is a very capable individual."

By removing any reference to race or age, you avoid making assumptions or generalizations based on those factors, and instead highlight the person's abilities and qualifications.