I can reproduce the issue with below builds.

virt-v2v-1.32.7-3.el7.x86_64
libguestfs-1.32.7-3.el7x86_64

Reproduce steps:

1:Prepare a RHEL 7.3 guest in ESX server。
2:Export the rhel7.3 guest as a ovf files.
3:Edit the ovf file: rhel7.3wk.ovf,and delete the <Name> tag under <VirtualSystem> and The content of <rasd:HostResource> does not have the "ovf:" prefix.
####
<VirtualSystem ovf:id="rhel7.3wk">
<Info>A virtual machine</Info>
<OperatingSystemSection ovf:id="80" ovf:version="7" vmw:osType="rhel7_64Guest">
<Info>The kind of installed guest operating system</Info>
####
<rasd:HostResource>/disk/vmdisk1</rasd:HostResource>
####
6:Repack the files,use v2v to convert the OVA file

#virt-v2v -i ova esx-rhel6.8-ova.tar -o null -on test
[ 0.0] Opening the source -i ova esx-rhel6.8-ova.tar
virt-v2v: error: could not parse ovf:Name from OVF document

If reporting bugs, run virt-v2v with debugging enabled and include the
complete output:

virt-v2v -v -x [...]



Try to verify this bug on below builds:
libguestfs-1.32.7-3.el7_3.2.x86_64
virt-v2v-1.32.7-3.el7_3.2.x86_64
rhv4.0: 4.0.6-3

Scenario 1：
1:Prepare a RHEL 7.3 guest in ESX server。
2:Export the rhel7.3 guest as a ovf files.
3:Edit the ovf file: rhel7.3wk.ovf,and delete the <Name> tag under <VirtualSystem> and The content of <rasd:HostResource> does not have the "ovf:" prefix.
####
<VirtualSystem ovf:id="rhel7.3wk">
<Info>A virtual machine</Info>
<OperatingSystemSection ovf:id="80" ovf:version="7" vmw:osType="rhel7_64Guest">
<Info>The kind of installed guest operating system</Info>
####
<rasd:HostResource>/disk/vmdisk1</rasd:HostResource>
####
4:Pack the files,use v2v to convert to rhv4.0.
virt-v2v -i ova rhel7.3-ova.tar -o rhev -os 10.73.131.93:/home/nfs_export -of qcow2
[ 0.0] Opening the source -i ova rhel7.3-ova.tar
virt-v2v: warning: could not parse ovf:Name from OVF document
[ 19.6] Creating an overlay to protect the source from being modified
[ 22.9] Initializing the target -o rhev -os 10.73.131.93:/home/nfs_export
[ 23.6] Opening the overlay
[ 34.5] Inspecting the overlay
[ 53.9] Checking for sufficient free disk space in the guest
[ 53.9] Estimating space required on target for each disk
[ 53.9] Converting Red Hat Enterprise Linux Server 7.2 (Maipo) to run on KVM
virt-v2v: This guest has virtio drivers installed.
[ 270.2] Mapping filesystem data to avoid copying unused and blank areas
[ 272.2] Closing the overlay
[ 273.7] Checking if the guest needs BIOS or UEFI to boot
[ 273.7] Assigning disks to buses
[ 273.7] Copying disk 1/1 to /tmp/v2v.19YKO9/ca31df01-aca7-441f-b10f-4f6a9b692684/images/daf947e3-bb8b-4c57-bf76-91e3edfe80c0/9f43d9c3-c575-4a10-9f0f-491b40ae4c4e (qcow2)
(100.00/100%)
[ 350.0] Creating output metadata
[ 350.1] Finishing off

5:Login rhevm and try to import the guest after finishing the conversion, but failed with below error:.
"Failed to import Vm rhel7.3-ova.tar to Data Center Default, Cluster Default".

 This issue is caused by an existing rhev4.0 bug :Bug 1378045
https://bugzilla.redhat.com/show_bug.cgi?id=1378045

 Because there is no MACAddress in the ovf configuration file which is exported from the VMware. there also is no mac address after converting this ova file by virt-v2v to export domain, checking the ovf file at export domain after v2v conversion, there is no mac address in ovf
<Item>
<rasd:InstanceId>f69e2151-ed9d-4c05-b783-d520ea3d29d3</rasd:InstanceId>
<rasd:Caption>Ethernet adapter on Network adapter 1</rasd:Caption>
<rasd:ResourceType>10</rasd:ResourceType>
<rasd:ResourceSubType>3</rasd:ResourceSubType>
<Type>interface</Type>
<rasd:Connection>Network adapter 1</rasd:Connection>
<rasd:Name>eth0</rasd:Name>
</Item>

6.If we manually add the mac address by editing the ovf file, the import the guest from export domain to data domain successfully

<Item>
<rasd:InstanceId>f69e2151-ed9d-4c05-b783-d520ea3d29d3</rasd:InstanceId>
<rasd:Caption>Ethernet adapter on Network adapter 1</rasd:Caption>
<rasd:ResourceType>10</rasd:ResourceType>
<rasd:ResourceSubType>3</rasd:ResourceSubType>
<Type>interface</Type>
<rasd:MACAddress>00:1a:4a:16:01:51</rasd:MACAddress>
<rasd:Connection>Network adapter 1</rasd:Connection>
<rasd:Name>eth0</rasd:Name>
</Item>

7.After finishing importing , power on the guest normally and checkpoint of  guest is passed

 

Scenario 2：

    1.Copy ova file which was edited by step3 of scenario1 to registered host of rhev4.0.
    2. Login rhv4.0,  Importing the ova file from rhev GUI-> virtual machines tab --> import --> select VMware virtual appliance (OVA)
    3.Guest can be import successful and checkpoint of guest is passed

 

Result:

According above verify result, the bug has been fixed by virt-v2v ,  so move the bug from ON_QA to VERIFIED

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2017-0099.html