...Is only possible when connecting through Tor. Or possible I2P or CDNJS, but I have never tried those two alternative methods, so I cannot comment about them.
--snip--
Which CDJNS you refer? I did quick search, but i only found centralized service offered by Cloudflare,
Sorry, it is actually called cjdns and there are some nodes for it listed at the end of this file: https://github.com/bitcoin/bitcoin/blob/master/contrib/seeds/nodes_main.txt#L893
It actually has nothing to do with cloudflare, but it seems to be an "encrypted IPV6 network" in a similar fashion to the other privacy networks such as I2P. You can see the source code for it here: https://github.com/cjdelisle/cjdns/
Although I'm not sure how anyone is supposed to use that in a world where everybody uses NAT for connecting to the internet.