Does exanic-capture really only work for the receive side? How can we capture the transmit side?

[bornlibra23]

I am having a problem capturing the TX using exanic-capture.
The manual says that it is only for reception
[https://www.cisco.com/c/en/us/td/docs/dcn/nexus3550/smartnic/sw/user-guide/cisco-nexus-smartnic-user-guide/config.html?bookSearch=true#:~:text=A%20utility%20called%20exanic%2Dcapture%20is%20provided%20that%20can%20be%20used%20to%20capture%20traffic%20received%20by%20an%20SmartNIC.]

Any suggestions?