81voltd is packaged in #postmarketOS now: https://pkgs.postmarketos.org/package/master/postmarketos/aarch64/81voltd
I am quite positive that 81voltd will land in postmarketOS 24.12 (or, maybe, before in a service pack, so that you can use stable - which does not suffer from 'breakage by upstream' as much as edge does).
Also, regarding Plasma Mobile: Plasma Mobile 6 is a lot better than previous releases, I am writing this from Plasma Mobile on OnePlus 6, happily accepting rare weirdness for a better virtual keyboard.