The release of qBittorrent v4.6.0 stable comes with I2P support. While experimental, we can still get a working torrent setup using qBittorrent now. qBittorrent-nox is the Web-UI only version, and currently it does not have configuration settings in the Web-UI for I2P settings. This guide will show you how to setup qBittorrent-nox and manually change the qBittorrent.conf file to allow for I2P torrenting!
That is the lacking area. There needs to be a development in the area of DHT crawlers and indexers to help find torrents on I2P like how btdigg works, but for I2P torrents. Hopefully one day.