I did not really check against your requirements, but this machine is under development in Berlin, Germany:
en: https://mntmn.com/media/reform_md/2020-05-08-the-much-more-personal-computer.html de: https://mntmn.com/media/reform_md/2020-05-12-mnt-reform-german-press-release.html AFAIK, the developers themselves run Debian and I like the fact, that it will use standard 18650 cells. (You might like to subscribe to the list, at least for a week.)
