I compiled the GSI overnight, its aosp_arm64_a Legacy GSI, because the ones I keep downloading are all August security patch and I wanted it a little more up to date. I got the source directly from google and built it myself. AB is now uploaded as aosp_arm64_ab. A only is also up as aosp_arm64_a-aosp. I ran it on my One Plus 5, NFC was buggy but the camera, ril, Bluetooth, wifi, and everything I tried out worked. this is vanilla, so its bare bones. no apps besides the basics, no mods or any customizing. As this is a GSI it should be useable on many devices, I can only help you with the devices that I own, pixel XL and one plus 5. If you have a device other then that, you will have to find help from someone knowledgeable about that device. I have had success using twrp and fastboot to flash the system image. I was told doing it via fastboot is the best, so you can disable verified boot, then flash, then format all in one shot. My device did not require me to disable the verify boot. From my end it was literally as simple as 3 commands via fastboot and then restart the device and I was in. I flashed a 50mb gapps package from xda here, and magisk. took some photos, connected my Bluetooth speaker, made a call. sent some texts, installed a few apps. I will be staying on stock. But only because my device has stock pie, and the theming from one plus far trumps google.
aosp_arm_a-userdebug and aosp_arm_ab-userdebug added