I'll include all 4 options, and the first (and most voted one) will be the default one.
By the way, I've been working on making some recolors.
The first one is Shiny Mewtwo as seen in Pokemon Stadium 2. Just bluish and less saturated.
This one would be Shiny Mewtwo as seen in Pokemon Co
eum. Purple parts are golden-like for this one.
The next one is similar, but more green. It's more like the PBR or GBA/DS Mewtwo.
This one is just a redish recolor, based on how Mewtwo looks when, in Stadium / Stadium 2, you give Mewtwo a nickname, and the result is redish. If you've played Stadium with your own pokemon from GBC, you know what I mean.
I'll make some other recolors when I get the time, which is very limited for me these days.