When Viptela interfaces are configured with a different "In Speed" and "Out Speed", NFA shows the same speed for both directions.
When looking at the Admin->Physical & Virtual page of NFA for Viptela you will see the same speed for "In Speed" and "Out Speed"
Release: RAIB1H99000-9.3-Network Flow Analysis-Interface Bundle-Hardware
Defect DE411209 has been opened for this and scheduled to be fixed in Netops 19.4
As a work around you can manually edit the In and Out speed from the Admin->Physical & Virtual page of NFA.