Apple - How to check VT-x status on MacBook Pro
According to Intel® Core™ i5-5257U Processor, it supports Intel Virtualization Technology (VT-x).
You can also from Terminal use the following command:
sysctl -a | grep machdep.cpu.features
If you see VMX in the output, then the CPU supports the Intel VT-x feature.
If you don't want to have to read through the output of CPU features and just see if VMX is there, then use: sysctl -a | grep -o VMX
From Intel-based Macs: Using VT-x virtualization technology:
Intel VT-x technology is enabled on Intel-based Macs. Make sure your Intel-based Mac has all available EFI updates installed; also update any third-party virtualization software.
Therefore there is no reason to check the status.
As to enabling/disabling, there is no direct user interface for that. Since it is enabled by default, the only way I can think of to disable it would be to hack the EFI Firmware. Which is not something I'd recommend doing!