Considering the 9000v is really only for labbing this isn't a huge deal, but I was able but to default an interface from enable mode; config mode is not required. I don't know if this is something I'd neccessarily consider a bug, but its something I'll definitely keep in mind when working with these images.

I tried this on a production Nexus 9372 running code 7.0.3.I2.4 and this wasn't possible, however /u/NetSysAdmin on reddit stated he was able to do this on Nexus 9508s running 7.0.3.I6.1 and 7.0.3.I7.1. The consensus in the reddit thread is that this isn't a huge concern, especially considering that the configuration can be modified from enable mode via commands such as write erase or copy start run.

I found it interesting because I've never encountered another Cisco platform (NX-OS, IOS, or otherwise) that allows an interface configuration to be defaulted without first being in config mode.

Update 2017.12.08

BugID provided by TAC: https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvg91620

Update 2017.11.28

This has been confirmed by the BU (via TAC) to be unexpected behavior and a BugID will be generated.
TAC Email

NX-OSv 9000 image version 7.0.3.I7.1

Configuring an interface as a trunk and adding a description, exiting config mode.

conf t
Enter configuration commands, one per line. End with CNTL/Z.
int e1/10
  description TEST-DEFAULT
  switchport mode trunk
  end
show run int e1/10

!Command: show running-config interface Ethernet1/10
!Time: Wed Nov 8 19:08:24 2017

version 7.0(3)I7(1)

interface Ethernet1/10
description TEST-DEFAULT
switchport mode trunk

Defaulting the interface from enable mode and validating.

default int e1/10
show run int e1/10

!Command: show running-config interface Ethernet1/10
!Time: Wed Nov 8 19:08:36 2017

version 7.0(3)I7(1)

interface Ethernet1/10