Bromite used to be great, but unfortunately the dev seems to have abandoned it.
I've seen people talking about Mull, Mulch, Fulguris and a couple others. I think Mulch is tied to a specific Android ROM, and the others are Firefox forks.
i left a big comment regarding this in another thread, TL;DR combination of brave on desktop and a lot of non-brave things on android, privacy browser + mull + DDG
i agree, but my unpopular opinion is that mozilla has also proven this repeatedly, with nothing and nobody being universally better. privacy people love firefox, but i spend a lot of time with each major version's release notes figuring out how to undo the new telemetry (increasing integration with pocket, firefox suggest, location that won't turn off).
my threat model is 'they're all evil, including mozilla', so there are additional rings around everything
DivestOS is the only Android ROM I know of that integrates the Mulch webview. But Tad (DivestOS dev) also builds standalone binaries of Mulch that can be installed independently- just add their repo into f-droid or something like droidify and you're good to go.
Link: https://divestos.org/fdroid/official
Yes, that's because it requires webview to be patched, it's the same reason that Vanadium is only available for GrapheneOS. They do use some of Vanadium's patches though.