but can I flash GSI on internal storage?I could install the Lineageos 19.1 GSI! I had to use this zip as a workaround ChonDoe_Flasher.zip, that allows flashing dynamic partitions even if the TWRP doesn't. I also made a treble overlay for this device (vendor.img), that fixes power profiles and all this stuff, ill upload it now if anyone is interested.
What doesnt work with the Lineage GSI or phh's AOSP is MTP and the fingerprint reader. Also i can't get encryption to work, the GSI crashes if i don't use multidisabler to remove encryption from the fstab. Everything else works flawlessly from my testing.
For file transfer i'm using ADB with this tool, it's even faster than MTP somehow Python ADB File Explorer