To be able to implement specs, the code has to follow the manageiq-content best practices and this requires changing the code. This BZ tracks the code change and specs implementation for /Transformation/Infrastructure/VM/Common/RestoreVmAttributes.
https://github.com/ManageIQ/manageiq-content/pull/385
Fixed! I can see destination vms have same attributes which we have on target before migration. Considered Tags, Cores, CPUs, MAC address. Verified on: 5.10.0.18.20181003162715_dfcff5a Thanks @Fabien!