In CC Open Source Blog you can find a detailed post about the plugin we made for easy search and use of CC-licensed images for WordPress, based on the Creative Commons Catalog API.
https://opensource.creativecommons.org/blog/entries/2019-07-24-cc-search-wp-plugin/
There are still many TODO tasks so, if you want to contribute, you can fork the plugin at Github: https://github.com/lenasterg/wp_ccsearch