Follow up:
Battery life is quite good on this laptop, whether on Windows or Xubuntu. I can’t tell what it looks like with Manja, since Manjaro is not my preferred distro and I uninstalled it as soon as I knew how to make Xubuntu work.
eMMC as /Home shouldn’t be an issue from my perspective. eMMC is always present, from time to time BIOS seems to “forget” the SSD, but no data losses whatsoever. I have all programs and OS’s on my SSD (Win10 and Xubuntu) and use the eMMC as “data exchange platform” only (pictures, documents, downloads…)
https://de.wikipedia.org/wiki/Ernst_Kuzorra