[Sony Xperia M2] titigab:
Hi, is it possible in any way to flash this rom (or 15.1) with a locked bootloader ?

I flashed EagleXperience 5.0b1 on locked bootloader (bootloader unlock allowed:no) using post #2 solution and EagleRootTool. I'm now with TWRP and EagleXperience5.0b1.

Trying to flash LOS14.1 or LOS15.1 results in error :

I:Starting command line thread
I:Set page: 'install'
I:Set page: 'flash_confirm'
I:Set page: 'flash_zip'
I:Set page: 'flash_zip'
Installing '/sdcard/lineage-14.1-20211029-UNOFFICIAL-eagle.zip'...
Checking for MD5 file...
Skipping MD5 check: no MD5 file found
I:Zip does not contain SELinux file_contexts file in its root.
I:Legacy property environment initialized.
Target: Sony/D2303/D2303:5.1.1/18.6.A.0.182/1807889774:user/release-keys
Target: Sony/D2303/D2303:5.1.1/18.6.A.0.182/1807889774:user/release-keys
could not detect filesystem for /dev/block/bootdevice/by-name/system, assuming ext4
could not detect filesystem for /dev/block/bootdevice/by-name/system, assuming ext4
mount: failed to mount /dev/block/bootdevice/by-name/system at /system: No such file or directory
mount: failed to mount /dev/block/bootdevice/by-name/system at /system: No such file or directory
about to run program [/tmp/install/bin/backuptool.sh] with 2 args
run_program: child exited with status 127
unmount of /system failed; no such volume
unmount of /system failed; no such volume
about to run program [/tmp/install/bin/otasigcheck.sh] with 1 args
Package cert index not found; skipping signature check...
Patching system image unconditionally...
performing update
Patching system image unconditionally...
open "/dev/block/bootdevice/by-name/system" failed: No such file or directory
script aborted: E1001: Failed to update system image.
E1001: Failed to update system image.
E:unknown command [log]
E:Error executing updater binary in zip '/sdcard/lineage-14.1-20211029-UNOFFICIAL-eagle.zip'
Error flashing zip '/sdcard/lineage-14.1-20211029-UNOFFICIAL-eagle.zip'
Updating partition details...
I:Data backup size is 655MB, free: 2815MB.
I:Unable to mount '/external_sd'
I:Actual block device: '', current file system: 'vfat'
I:Unable to mount '/usb-otg'
I:Actual block device: '', current file system: 'vfat'
...done
I:Set page: 'flash_done'
I:Set page: 'clear_vars'
I:Set page: 'install'
I:Set page: 'flash_confirm'
I:Set page: 'flash_zip'
I:Set page: 'flash_zip'
Installing '/sdcard/lineage-15.1-20220311-UNOFFICIAL-eagle.zip'...
Checking for MD5 file...
Skipping MD5 check: no MD5 file found
I:Zip does not contain SELinux file_contexts file in its root.
I:Legacy property environment initialized.
selinux_android_file_context: Error getting file context handle (No such file or directory)
script aborted: E3004: This package is for device: D2302,D2303,D2305,D2306,D2403,D2406,eagle; this device is .
Warning: No file_contextsE3004: This package is for device: D2302,D2303,D2305,D2306,D2403,D2406,eagle; this device is .E:unknown command [log]
E:Error executing updater binary in zip '/sdcard/lineage-15.1-20220311-UNOFFICIAL-eagle.zip'
Error flashing zip '/sdcard/lineage-15.1-20220311-UNOFFICIAL-eagle.zip'
Updating partition details...
I:Data backup size is 655MB, free: 2815MB.
I:Unable to mount '/external_sd'
I:Actual block device: '', current file system: 'vfat'
I:Unable to mount '/usb-otg'
I:Actual block device: '', current file system: 'vfat'
...done
I:Set page: 'flash_done'
I:Set page: 'clear_vars'

I know it's a pretty old device now but is there any solution to go Google Free rom ?

Thanks