Here is YuzukiTsuru's hardware project organization, including open source hardware design, software source code, related documents, and some development kits
Unless specifically stated, you can use the hardware design files of these projects under the CERN Open Hardware Licence Version 2 - Strongly Reciprocal License or CERN Open Hardware Licence Version 2 - Permissive depends on which project
All hardware designs use easyeda: https://pro.easyeda.com/editor