Heard some people were interested in starting this project, might as well post what I recall here.

First of all, I haven't actually started to mod the mons in. My goal has been to document most of the file structures first, make clean tools after and finally batch port the mons into the game.

The good news:
Pokemon Home is a great resource for this.
The Switch version of home has a 1-to-1 personal data file that just works when dragged and dropped to SWSH. This means that data-wise, the national dex mod is "complete".

The mobile version has decompileable shaders, easy to follow scripts for more complicated mons (Spinda) and very high resolution textures.

The bad news:
Right now the biggest stop factor for me is shader decompilation and making a decent tool for animation import/export.

Additionally, some unforseen unity extraction issues have stopped us from decrypting certain mons from Home (I forget exactly which ones) which required me to track down the issue. It stems from LZ4HC implementations which I'm not familiar with.

Where you can help:
Right now, most of what I have has been properly (to my standards) documented at https://github.com/rh-hideout/rhh-docs

We're always looking for contributors on the bnsh area, home decryption or people who're willing to help out with proper tools for this.

The plan:
1) Finish documenting relevant structs.
2) Make decent cli tools to convert from an intermediate format to gflib3.0
3) Make decent cli tools to convert from unity to intermediate formats
4) ????
5) Profit