If you want to get started, you should have a hacked switch with SMO 1.0.0 dumped as that's what most of the community is using for modding.
Make sure you have at least some knowledge of C++ before doing code mods.
You can find existing mods on GameBanana.
- EditorCore/OdysseyEditor
- Switch Toolbox (edits files directly, use editorcore for )
Starlight forks can be used as reference (or templates) for your own projects.
- Bryce's Starlight fork
- CraftyBoss's Starlight fork with Custom Actors
- CraftyBoss's Starlight fork with Layout Editing
- Sead (Nintendo's in-house C++ standard library)
- Work-in-progress Odyssey decompilation project
- Archived Odyssey decompilation project
Here are discord servers where you can ask for help or share your creations. Remember to not to be rude or harrass anyone in these servers.