I use SeaMonkey as my usenet client. I prefer it to anything else for that.

Porn torrents on i2p work. But i2p is too slow for streaming.

I2P is for whatever people put on it. It’s all the Internet services that already can exist, specifically behind a piece of software such as i2pd for example. It’s free, just setup i2p software on a computer. Then you can make some local services visible to it, for example a web server.

You can do whatever you want on i2p. Nobody knows who you are.