Pyukumuku: Evolves into a water/fighting type, growing additional "spikes" as well as tentacles which it uses to defend itself. Its intestines have become more muscular and arm like. It has abandoned its old rigid ways, and has adopted more of a "go with the flow" philosophy. It's more of a bulky fighter type mon, with emphasis on absorbing its opponent's strikes and hitting back harder. Still has innards out.

Mimikyu: Still is ghost/fairy with disguise.
Becomes a shadowy puppet master controlling several disguises of different pokemon. Although it has grown too big for the pikachu costume, the ripped remains of the costume still are present on its head. It will be as angsty as mimikyu already is.

Salandit: Fire/Poison with Corrosion. male/female forms of evolution (kinda like meowstic).
Males are black, and are more komodo dragon like. There are purple accents that run down its body up to its face, and has 2 purple fangs. The fiery part of its tale has now become more active, looking more volacano-like, gushing lava. Fast, Offensive mon.
Females are smaller, and are white. The fire marks from its tail have become purple, and ooze pheromones and toxins. it has small strips of red down its body, that emit flames. Fast, utility mon with emphasis on spreading status.

Comment with your own autistic evolution ideas.