Hello,
I’ve modded my Arturia Keylab Essential Mk3 recently, maybe that post will help someone.
You may ask, why I bought this in the first place? Well, I found a stock B offer which was 40€ cheaper, and thanks to that I got an offer for V collection for 150€. Not so bad 
Action was really bizarre, there was a resistancr halfway through, I was really wondering why is that. When I disassmbled the keyboard, I’ve found out that it is a springless action. Because of that the key was so light that a contact rubber caused a noticable resistance.
I saw once a video on yt where a guy created “rhodes” from reface cp and midi controller. In order to make keybed more rhodes-like, he added some wheel weights to the keys. So I decided to do some modding, and add such weights to my keyboard. It’s worth notice that keylab mk1 (not essential) have such metal weights on keys, however there were some springs.
Disassembly is a little bit tricky, because there is a hidden screw under the middel rubber feet, and there are also some latches on the keybed side. The next step is to remove the ribbon connector, which is easy as well, but I suggest to mark them, or at least take a photo.
Removal of keys is very easy, just unscrew the section and move it slightly down. Attaching weights for white keys is trivial, however for black keys I had to use tweezers.
The feel of the kehbed is definetely better, maybe in the future I will add a third weight for black keys, and change the damper felt, so the keys will be quiter.
Overally, mod costed me 8€ and I left with 1000 more 2.5g weights 
So I can recommend it anyone who would like to make keyboard action semi-weighted
