It is possible to load configuration also from data packs.

In order to configure mod using data pack create specific file structure in your data pack.

Example data pack structure

example
├── pack.mcmeta
├── pack.png
└── data
    └── example
        └── puffish_skills
            ├── categories
            │   ├── category_1
            │   │   ├── category.json
            │   │   ├── connections.json
            │   │   ├── definitions.json
            │   │   ├── experience.json
            │   │   └── skills.json
            │   └── category_2
            │       ├── category.json
            │       ├── connections.json
            │       ├── definitions.json
            │       ├── experience.json
            │       └── skills.json
            └── config.json