pokered and its derivatives have been on github for many years. As long as it stays to a small scope Nintendo seems content to let these small projects be. That could change at any second though. Clone while you can.

The copyright status of explicitly decompiled source is still unproven in the US, as far as I know. SAS vs World Programming seems to indicate that decompilation followed by reimplementation over a wall is probably not infringing, but I don't think a case has been tried around the direct output of a decompiler (i.e. OpenRCT, this SM64, etc.).

There is pretty-much only copyrighted material in this repo.

Copyright is not purely literal, especially when it's copyright of computer code...

Obviously IANAL, but my understanding was that conversion and translation is deemed to be under the same copyright as the source.

The models and sounds aren't copyrighted? Because they are totally within the GitHub, there...

I didn't look through the repo, but given that the linked README talks about needing an original version of the ROM in order to extract assets, I would guess they're not in there?

The models certainly are. Don't think the textures are.

A number of assets, including textures, audio, and prerecorded demos, have been stripped out of this release.