>>9908370They didn't make Keshi for the first 3 games. They started with 4 and changed some of the scale with 7, but a number of the later ones are still pretty compatible. The Keshi line is the best thing to collect if you're a Mega Man fan; it just has the most variety and best character selection.
I was considering trying to sculpt my own mini-figures just to do ones from 2 and 3.
https://www.youtube.com/watch?v=ZT9DST_M_g8