[Custom Feature Question] New Feature Like Shadow Pokémon

[Atlat]

So, I've been working on what is similar to a shadow Pokémon, yet fundamentally different. Plans are still somewhat in the planning phase, but right now what I need is to be able to get types and moves (the moves part is essentially the same as the shadow mons, so that should be fine) from a .txt file so that the Pokémon is re-typed as that (preferably with a tint that indicates the Pokémon's new type). Before you say anything like "why not just create alternate forms," to me, this is just the beginning. There will be features in battle that are exclusive to these special variants (unnamed as of now).

Also need to figure out the code for how to get the form sprites to work. For now, they continue to not adjust to the new versions despite me modifying the Species_Files script in order to include them.

Bonus points to those that are able to do more than just types (like stats, EVs, friendship levels, held items, etc.).