For anyone else reading this, librera reader + sherpaTTS are both FOSS android apps and can read anything librera can open on an ad-hoc basis, with no need to futz with files, just load your ebook bookmark and hit play.
SherpaTTS has a bunch of different models (piper/coqui) with a ton of voices/languages. There's a slight but tolerable delay with piper high models but low is realtime.
Any plans to make a Chrome extension variant? Been looking for a high quality and cheap TTS extension for ages (like ElevenLabs Human Reader, except with less absurd pricing)
I din't think of that, interesting idea. What I'm focusing right now is long-form content for more offline-ish listening, but maybe a plugin could work to load longer texts, but I'm not working on a screen reader atm.