I use water and Eezox mostly. Well, Eezox always, but the solvent varies.
I've used Hoppes BP solvent, CVA stuff, homemade “moose milk“ (tapping fluid and water) soap and water, t/c number 13, (smells nice) windex, olive oil, olive oil and beeswa mix, jojoba oil, plain hot water, cold water, and I’m sure I’ve forgotten others. They all worked to one degree or another, most anything water based is fine.
Protecting the metal after the black powder fouling is removed is the most important part of the process IMO.. I’ve not found anything better than Eezox to date, it works and dries to a non oily film.