I want to install this plugin too but it's not showing up in the registry either.
nodebb-plugin-topic-badges
NodeBB Topic Badges - Allows users to label a topic with a badge by prefixing their title in square brackets. Latest version: 0.1.1, last published: 10 years ago. Start using nodebb-plugin-topic-badges in your project by running `npm i nodebb-plugin-topic-badges`. There are no other projects in the npm registry using nodebb-plugin-topic-badges.
npm (www.npmjs.com)