Why there's still no voice over functionality ?
I tried it on ubuntu 17.10 64(mate), it won't work, I tried it on Mandriva based distro it won't work...
it's not like I have rare hardware or anything....

I use Ardour 5 for voice-overs. I prefer it because I can use real-time effects and don't need to edit my recordings afterwards. I have it set up to use the following effects, in order:

GxExpander (expander - reduces volume below the threshold - actually works better than a noisegate for my set up)
GxCompressor (compressor - using a small amount of compression to keep my voice level fairly even)
Distrho 3 band EQ (I have a very bass-heavy voice, so I drop the bass down a little and boost the treble a little)

Of course, another alternative is Audacity, which is very good.

I'm just trying to get a one stop comfortable voice over, without deliberate pain in the **** setup, which doesn't work whatever you do...
I have even install Ubuntu Studio, which promised to work Ardour and Kdenlive out of the box. Still nothing. And I have NO exotic rig.

I use KXStudio - both Ardour 5 and Kdenlive are set up and work right out of the box - I recommend that you try it. Ardour doesn't play nice with Pulseaudio, so it isn't set up by default in KXStudio. Jack runs at boot and uses Alsa for sound.

It's based on Ubuntu 14.04.5, so it's a bit older and the Kdenlive version is 9.10. I did try Ubuntu Studio and had issues straight away, so I switched to KXStudio - which is the best one, in my opinion. I haven't tried recording my voice with Kdenlive, so I don't know if that works in the 9.10 version.

Please respond to this, I am using Ubuntu 16, I did a research and purchased Nuemann TLM 103 based on this article
https://pixengo.com/best-voice-over-microphone/
but it is not working, I am not able to record anything.

Not sure whether there is one stop voice over solution. As for not being able to record anything you might want to install pavucontrol to see whether all the channels are set up properly although the systemsettings interface is also not bad. I used audacity in the olden days which is almighty but requires a bit of setting up.