Don't know if solar system only counts as space opera, but @sjgames 's "GURPS Transhuman Space" setting has a very pre-WWI vibe, with the EU, US, China, The Transpacific Socialist Alliance, the Pacific Rim Alliance, and India all as significant powers with interests throughout the solar system.
Plus infosocialists, and two flavors of anarchists.
Includes computer AIs, artificial lifeforms, genetically engineered everything, and human uploads.




