Enable "OEM Unlock" via build.prop edit! I need to bypass fingerprint lock on an Samsung Galaxy A8 (A800F) phone in order to save the data stored on the phone, FRP was ON but i managed to fix it and change it to OFF, Now i can flash any custom recovery i want, but it won't boot into recovery (RECOVERY IS NOT A SEANDROID ENFORCING), That error because of the OEM Unlock option isn't activated, So my question is there any other way to enable that option without getting into settings?, can i just modify the stock system.img and add a line to the build.prop to enable that option?
OEM unlock is not a line in the build.prop file or any other user accessible file that we know of, it is a hidden flag somewhere (probably encrypted) and not in the ROM itself (flashing a custom ROM or completely wiping all visible partitions does not change the setting's state). Unfortunately, if you can't somehow access the Developer menu, you will not be able to unlock the bootloader.

The answer is that as of now, this is not possible with this device.