You can get there by clicking the Customize button tab at the bottom (middle section) of the Invoice, Estimate, and Sales Receipt. Select “More” > Check boxes to show Billable to include employee name, hours and rate.
You can also get there from the Company Gear (upper-corner) > Company Settings under Settings header > Sales > Customize > Customize look and feel button > Select More > Check boxes to show Billable to include employee name, hours and rate.
NOTE: This newly added feature is not yet available on all newer QBO versions. That’s what I heard from actual users.