Isn't Mobian a debian with additionnal packages to have a mobile interface?
The mobian installation instructions are hosted on debian's wiki: https://wiki.debian.org/InstallingDebianOn/PINE64/PineTab2
The mobian installation instructions are hosted on debian's wiki: https://wiki.debian.org/InstallingDebianOn/PINE64/PineTab2
That being said, neither the Pinetab/Pinetab2 are very well supported, I would not recommend.