Either you are using contradictory terms, or I am misunderstanding what you are wanting to do.
NIC Teaming on a server, with one NIC active and one NIC standby, is NOT port-channeling. So, if you configured your NIC team for Network Fault Tolerance, they would not be port-channeled. This should not be a problem if the server is connected to two different FEX.
NIC Teaming on the server using either Switch Assisted Load Balancing w/Fault Tolerance, or 802.3ad Dynamic w/Fault Tolerance results in both server NICs being active all the time. This will require matching port-channel configuration on the switch/FEX.
http://ramazancan.wordpress.com/2011/08/06/how-to-configure-nic-teaming-with-hp-proliant-and-cisco-or-procurve-switch-infrastructure/
As far as connecting a server via port-channel across two different FEX, I didn't see anything in configuration guidelines to indicate that it's not a supported configuration.
http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/6_x/nx-os/interfaces/configuration/guide/if_cli/if_portchannel.html#pgfId-1888267
You cannot port-channel two Nexus ports together which are on different hardware (i.e., one port on an M1 module and another on an M2 module, or one on an F1 module and another on an M1 module, etc). So, since LACP processing is offloaded to the FEX, perhaps there is an unwritten guideline that says both FEX need to be of the same type, and possibly uplinked to the same type of module on the Nexus 7K, in order to support port-channel across different FEX.
-rb
